Microsoft Patch Tuesday, February 2023 Edition

February 14, 2023
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Microsoft is sending the world a whole bunch of love today, in the form of patches to plug dozens of security holes in its Windows operating systems and other software. This year’s special Valentine’s Day Patch Tuesday includes fixes for a whopping three different “zero-day” vulnerabilities that are already being used in active attacks.

Microsoft’s security advisories are somewhat sparse with details about the zero-day bugs. Redmond flags CVE-2023-23376 as an “Important” elevation of privilege vulnerability in the Windows Common Log File System Driver, which is present in Windows 10 and 11 systems, as well as many server versions of Windows.

“Sadly, there’s just a little solid information about this privilege escalation,” said Dustin Childs, head of threat awareness at Trend Micro’s Zero Day Initiative. “Microsoft does note that the vulnerability would allow an attacker to exploit code as SYSTEM, which would allow them to completely take over a target. This is likely being chained with a remote code execution bug to spread malware or ransomware. Considering this was discovered by Microsoft’s Threat Intelligence Center, it could mean it was used by advanced threat actors. Either way, make sure you test and roll these fixes quickly.”

The zero-day CVE-2023-21715 is a weakness in Microsoft Office that Redmond describes as a “security feature bypass vulnerability.”

“Microsoft lists this as under active exploit, but they offer no info on how widespread these exploits may be,” Childs said. “Based on the write-up, it sounds more like a privilege escalation than a security feature bypass, but regardless, active attacks in a common enterprise application shouldn’t be ignored. It’s always alarming when a security feature is not just bypassed but exploited. Let’s hope the fix comprehensively addresses the problem.”

The third zero-day flaw already seeing exploitation is CVE-2023-21823, which is another elevation of privilege weakness — this one in the Microsoft Windows Graphic component. Researchers at cybersecurity forensics firm Mandiant were credited with reporting the bug.

Kevin Breen, director of cyber threat research at Immersive Labs, pointed out that the security bulletin for CVE-2023-21823 specifically calls out OneNote as being a vulnerable component for the vulnerability.

“In recent weeks, we have seen an increase in the use of OneNote files as part of targeted malware campaigns,” Breen said. “Patches for this are delivered via the app stores and not through the typical formats, so it’s important to double check your organization’s policies.” Continue reading →

U.S., U.K. Sanction 7 Men Tied to Trickbot Hacking Group

February 9, 2023
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Authorities in the United States and United Kingdom today levied financial sanctions against seven men accused of operating “Trickbot,” a cybercrime-as-a-service platform based in Russia that has enabled countless ransomware attacks and bank account takeovers since its debut in 2016. The U.S. Department of the Treasury says the Trickbot group is associated with Russian intelligence services, and that this alliance led to the targeting of many U.S. companies and government entities.

Initially a stealthy trojan horse program delivered via email and used to steal passwords, Trickbot evolved into “a highly modular malware suite that provides the Trickbot Group with the ability to conduct a variety of illegal cyber activities, including ransomware attacks,” the Treasury Department said.

A spam email from 2020 containing a Trickbot-infected attachment. Image: Microsoft.

“During the height of the COVID-19 pandemic in 2020, Trickbot targeted hospitals and healthcare centers, launching a wave of ransomware attacks against hospitals across the United States,” the sanctions notice continued. “In one of these attacks, the Trickbot Group deployed ransomware against three Minnesota medical facilities, disrupting their computer networks and telephones, and causing a diversion of ambulances. Members of the Trickbot Group publicly gloated over the ease of targeting the medical facilities and the speed with which the ransoms were paid to the group.”

Only one of the men sanctioned today is known to have been criminally charged in connection with hacking activity. According to the Treasury Department, the alleged senior leader of the Trickbot group is 34-year-old Russian national Vitaly “Bentley” Kovalev.

A New Jersey grand jury indicted Kovalev in 2012 after an investigation by the U.S. Secret Service determined that he ran a massive “money mule” scheme, which used phony job offers to trick people into laundering money stolen from hacked small to mid-sized businesses in the United States. The 2012 indictment against Kovalev relates to cybercrimes he allegedly perpetrated prior to the creation of Trickbot.

BOTNET, THE MOVIE

In 2015, Kovalev reportedly began filming a movie in Russia about cybercrime called “Botnet.” According to a 2016 story from Forbes.ru, Botnet’s opening scene was to depict the plight of Christina Svechinskaya, a Russian student arrested by FBI agents in September 2010.

Christina Svechinskaya, a money mule hired by Bentley who was arrested by the FBI in 2010.

Svechinskaya was one of Bentley’s money mules, most of whom were young Russian students on temporary travel visas in the United States. She was among 37 alleged mules charged with aiding an international cybercrime operation — basically, setting up phony corporate bank accounts for the sole purpose of laundering stolen funds.

Although she possessed no real hacking skills, Svechinskaya’s mugshot and social media photos went viral online and she was quickly dubbed “the world’s sexiest computer hacker” by the tabloids.

Kovalev’s Botnet film project was disrupted after Russian authorities raided the film production company’s offices as part of a cybercrime investigation. In February 2016, Reuters reported that the raid was connected to a crackdown on “Dyre,” a sophisticated trojan that U.S. federal investigators say was the precursor to the Trickbot malware. The Forbes.ru article cited sources close to the investigation who said the film studio was operating as a money-laundering front for the cybercrooks behind Dyre. Continue reading →

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KrebsOnSecurity in Upcoming Hulu Series on Ashley Madison Breach

February 7, 2023
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KrebsOnSecurity will likely have a decent amount of screen time in an upcoming Hulu documentary series about the 2015 megabreach at marital infidelity site Ashley Madison. While I can’t predict what the producers will do with the video interviews we shot, it’s fair to say the series will explore compelling new clues as to who may have been responsible for the attack.

The new docuseries produced by ABC News Studios and Wall to Wall Media is tentatively titled, “The Ashley Madison Affair,” and is slated for release on Hulu in late Spring 2023. Wall to Wall Media is part of the Warner Bros. International Television Production group.

“Featuring exclusive footage and untold firsthand interviews from those involved, the series will explore infidelity, morality, cyber-shaming and blackmail and tell the story of ordinary people with big secrets and a mystery that remains unsolved to this day,” reads a Jan. 12, 2023 scoop from The Wrap.

There are several other studios pursuing documentaries on the Ashley Madison breach, and it’s not hard to see why. On July 19, 2015, a hacker group calling itself The Impact Team leaked Ashley Madison internal company data, and announced it would leak all user data in a month unless Ashley Madison voluntarily shut down before then.

A month later, The Impact Team published more than 60 gigabytes of data, including user names, home addresses, search history, and credit card transaction records. The leak led to the public shaming and extortion of many Ashley Madison users, and to at least two suicides. It’s impossible to say how many users lost their jobs or marriages as a result of the breach.

I’m aware that there are multiple studios working on Ashley Madison documentaries because I broke the story of the breach in 2015, and all of those production houses approached me with essentially the same pitch: It would be a shame if your voice wasn’t included in our project.

What stood out about the inquiry from Wall to Wall was that their researchers had already gathered piles of clues about the breach that I’d never seen before.

I’d assumed that participating in their documentary would involve sitting for a few interviews about known historical facts related to the breach. But when Wall to Wall shared what they’d found, I was hooked, and spent several weeks investigating those leads further.

The result was a collaborative research effort revealing key aspects of the breach that have somehow escaped public notice over the years.

I won’t go into detail on what we discovered until the Hulu series is ready for release. Also, I am not privy to what they will produce with the interviews I gave. I can’t say that what we found untangles everything about the breach that was previously unknown, but it sure explains a lot.

Finland’s Most-Wanted Hacker Nabbed in France

February 5, 2023
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Julius “Zeekill” Kivimäki, a 25-year-old Finnish man charged with extorting a local online psychotherapy practice and leaking therapy notes for more than 22,000 patients online, was arrested this week in France. A notorious hacker convicted of perpetrating tens of thousands of cybercrimes, Kivimäki had been in hiding since October 2022, when he failed to show up in court and Finland issued an international warrant for his arrest.

In late October 2022, Kivimäki was charged (and “arrested in absentia,” according to the Finns) with attempting to extort money from the Vastaamo Psychotherapy Center. In that breach, which occurred in October 2020, a hacker using the handle “Ransom Man” threatened to publish patient psychotherapy notes if Vastaamo did not pay a six-figure ransom demand.

Vastaamo refused, so Ransom Man shifted to extorting individual patients — sending them targeted emails threatening to publish their therapy notes unless paid a 500-euro ransom.

When Ransom Man found little success extorting patients directly, they uploaded to the dark web a large compressed file containing all of the stolen Vastaamo patient records.

But as documented by KrebsOnSecurity in November 2022, security experts soon discovered Ransom Man had mistakenly included an entire copy of their home folder, where investigators found many clues pointing to Kivimäki’s involvement. From that story:

“Among those who grabbed a copy of the database was Antti Kurittu, a team lead at Nixu Corporation and a former criminal investigator. In 2013, Kurittu worked on an investigation involving Kivimäki’s use of the Zbot botnet, among other activities Kivimäki engaged in as a member of the hacker group Hack the Planet (HTP).”

“It was a huge opsec [operational security] fail, because they had a lot of stuff in there — including the user’s private SSH folder, and a lot of known hosts that we could take a very good look at,” Kurittu told KrebsOnSecurity, declining to discuss specifics of the evidence investigators seized. “There were also other projects and databases.”

According to the French news site actu.fr, Kivimäki was arrested around 7 a.m. on Feb. 3, after authorities in Courbevoie responded to a domestic violence report. Kivimäki had been out earlier with a woman at a local nightclub, and later the two returned to her home but reportedly got into a heated argument.

Police responding to the scene were admitted by another woman — possibly a roommate — and found the man inside still sleeping off a long night. When they roused him and asked for identification, the 6′ 3″ blonde, green-eyed man presented an ID that stated he was of Romanian nationality.

The French police were doubtful. After consulting records on most-wanted criminals, they quickly identified the man as Kivimäki and took him into custody. Continue reading →

Experian Glitch Exposing Credit Files Lasted 47 Days

January 25, 2023
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On Dec. 23, 2022, KrebsOnSecurity alerted big-three consumer credit reporting bureau Experian that identity thieves had worked out how to bypass its security and access any consumer’s full credit report — armed with nothing more than a person’s name, address, date of birth, and Social Security number. Experian fixed the glitch, but remained silent about the incident for a month. This week, however, Experian acknowledged that the security failure persisted for nearly seven weeks, between Nov. 9, 2022 and Dec. 26, 2022.

The tip about the Experian weakness came from Jenya Kushnir, a security researcher living in Ukraine who said he discovered the method being used by identity thieves after spending time on Telegram chat channels dedicated to cybercrime.

Normally, Experian’s website will ask a series of multiple-choice questions about one’s financial history, as a way of validating the identity of the person requesting the credit report. But Kushnir said the crooks learned they could bypass those questions and trick Experian into giving them access to anyone’s credit report, just by editing the address displayed in the browser URL bar at a specific point in Experian’s identity verification process.

When I tested Kushnir’s instructions on my own identity at Experian, I found I was able to see my report even though Experian’s website told me it didn’t have enough information to validate my identity. A security researcher friend who tested it at Experian found she also could bypass Experian’s four or five multiple-choice security questions and go straight to her full credit report at Experian.

Experian acknowledged receipt of my Dec. 23 report four days later on Dec. 27, a day after Kushnir’s method stopped working on Experian’s website (the exploit worked as long as you came to Experian’s website via annualcreditreport.com — the site mandated to provide a free copy of your credit report from each of the major bureaus once a year).

Experian never did respond to official requests for comment on that story. But earlier this week, I received an otherwise unhelpful letter via snail mail from Experian (see image above), which stated that the weakness we reported persisted between Nov. 9, 2022 and Dec. 26, 2022.

“During this time period, we experienced an isolated technical issue where a security feature may not have functioned,” Experian explained. Continue reading →

Administrator of RSOCKS Proxy Botnet Pleads Guilty

January 24, 2023
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Denis Emelyantsev, a 36-year-old Russian man accused of running a massive botnet called RSOCKS that stitched malware into millions of devices worldwide, pleaded guilty to two counts of computer crime violations in a California courtroom this week. The plea comes just months after Emelyantsev was extradited from Bulgaria, where he told investigators, “America is looking for me because I have enormous information and they need it.”

A copy of the passport for Denis Emelyantsev, a.k.a. Denis Kloster, as posted to his Vkontakte page in 2019.

First advertised in the cybercrime underground in 2014, RSOCKS was the web-based storefront for hacked computers that were sold as “proxies” to cybercriminals looking for ways to route their Web traffic through someone else’s device.

Customers could pay to rent access to a pool of proxies for a specified period, with costs ranging from $30 per day for access to 2,000 proxies, to $200 daily for up to 90,000 proxies.

Many of the infected systems were Internet of Things (IoT) devices, including industrial control systems, time clocks, routers, audio/video streaming devices, and smart garage door openers. Later in its existence, the RSOCKS botnet expanded into compromising Android devices and conventional computers.

In June 2022, authorities in the United States, Germany, the Netherlands and the United Kingdom announced a joint operation to dismantle the RSOCKS botnet. But that action did not name any defendants.

Inspired by that takedown, KrebsOnSecurity followed clues from the RSOCKS botnet master’s identity on the cybercrime forums to Emelyantsev’s personal blog, where he went by the name Denis Kloster. The blog featured musings on the challenges of running a company that sells “security and anonymity services to customers around the world,” and even included a group photo of RSOCKS employees.

“Thanks to you, we are now developing in the field of information security and anonymity!,” Kloster’s blog enthused. “We make products that are used by thousands of people around the world, and this is very cool! And this is just the beginning!!! We don’t just work together and we’re not just friends, we’re Family.”

But by the time that investigation was published, Emelyantsev had already been captured by Bulgarian authorities responding to an American arrest warrant. At his extradition hearing, Emelyantsev claimed he would prove his innocence in an U.S. courtroom.

“I have hired a lawyer there and I want you to send me as quickly as possible to clear these baseless charges,” Emelyantsev told the Bulgarian court. “I am not a criminal and I will prove it in an American court.” Continue reading →

New T-Mobile Breach Affects 37 Million Accounts

January 19, 2023
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T-Mobile today disclosed a data breach affecting tens of millions of customer accounts, its second major data exposure in as many years. In a filing with federal regulators, T-Mobile said an investigation determined that someone abused its systems to harvest subscriber data tied to approximately 37 million current customer accounts.

Image: customink.com

In a filing today with the U.S. Securities and Exchange Commission, T-Mobile said a “bad actor” abused an application programming interface (API) to hoover up data on roughly 37 million current postpaid and prepaid customer accounts. The data stolen included customer name, billing address, email, phone number, date of birth, T-Mobile account number, as well as information on the number of customer lines and plan features.

APIs are essentially instructions that allow applications to access data and interact with web databases. But left improperly secured, these APIs can be leveraged by malicious actors to mass-harvest information stored in those databases. In October, mobile provider Optus disclosed that hackers abused a poorly secured API to steal data on 10 million customers in Australia.

T-Mobile said it first learned of the incident on Jan. 5, 2023, and that an investigation determined the bad actor started abusing the API beginning around Nov. 25, 2022. The company says it is in the process of notifying affected customers, and that no customer payment card data, passwords, Social Security numbers, driver’s license or other government ID numbers were exposed.

In August 2021, T-Mobile acknowledged that hackers made off with the names, dates of birth, Social Security numbers and driver’s license/ID information on more than 40 million current, former or prospective customers who applied for credit with the company. That breach came to light after a hacker began selling the records on a cybercrime forum.

Last year, T-Mobile agreed to pay $500 million to settle all class action lawsuits stemming from the 2021 breach. The company pledged to spend $150 million of that money toward beefing up its own cybersecurity.

In its filing with the SEC, T-Mobile suggested it was going to take years to fully realize the benefits of those cybersecurity improvements, even as it claimed that protecting customer data remains a top priority.

“As we have previously disclosed, in 2021, we commenced a substantial multi-year investment working with leading external cybersecurity experts to enhance our cybersecurity capabilities and transform our approach to cybersecurity,” the filing reads. “We have made substantial progress to date, and protecting our customers’ data remains a top priority.”

Despite this being the second major customer data spill in as many years, T-Mobile told the SEC the company does not expect this latest breach to have a material impact on its operations.

While that may seem like a daring thing to say in a data breach disclosure affecting a significant portion of your active customer base, consider that T-Mobile reported revenues of nearly $20 billion in the third quarter of 2022 alone. In that context, a few hundred million dollars every couple of years to make the class action lawyers go away is a drop in the bucket. Continue reading →

Thinking of Hiring or Running a Booter Service? Think Again.

January 17, 2023
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Most people who operate DDoS-for-hire businesses attempt to hide their true identities and location. Proprietors of these so-called “booter” or “stresser” services — designed to knock websites and users offline — have long operated in a legally murky area of cybercrime law. But until recently, their biggest concern wasn’t avoiding capture or shutdown by the feds: It was minimizing harassment from unhappy customers or victims, and insulating themselves against incessant attacks from competing DDoS-for-hire services.

And then there are booter store operators like John Dobbs, a 32-year-old computer science graduate student living in Honolulu, Hawaii. For at least a decade until late last year, Dobbs openly operated IPStresser[.]com, a popular and powerful attack-for-hire service that he registered with the state of Hawaii using his real name and address. Likewise, the domain was registered in Dobbs’s name and hometown in Pennsylvania.

Dobbs, in an undated photo from his Github profile. Image: john-dobbs.github.io

The only work experience Dobbs listed on his resume was as a freelance developer from 2013 to the present day. Dobbs’s resume doesn’t name his booter service, but in it he brags about maintaining websites with half a million page views daily, and “designing server deployments for performance, high-availability and security.”

In December 2022, the U.S. Department of Justice seized Dobbs’s IPStresser website and charged him with one count of aiding and abetting computer intrusions. Prosecutors say his service attracted more than two million registered users, and was responsible for launching a staggering 30 million distinct DDoS attacks.

The government seized four-dozen booter domains, and criminally charged Dobbs and five other U.S. men for allegedly operating stresser services. This was the Justice Department’s second such mass takedown targeting DDoS-for-hire services and their accused operators. In 2018, the feds seized 15 stresser sites, and levied cybercrime charges against three men for their operation of booter services.

Dobbs’s booter service, IPStresser, in June 2020. Image: archive.org.

Many accused stresser site operators have pleaded guilty over the years after being hit with federal criminal charges. But the government’s core claim — that operating a booter site is a violation of U.S. computer crime laws — wasn’t properly tested in the courts until September 2021.

That was when a jury handed down a guilty verdict against Matthew Gatrel, a then 32-year-old St. Charles, Ill. man charged in the government’s first 2018 mass booter bust-up. Despite admitting to FBI agents that he ran two booter services (and turning over plenty of incriminating evidence in the process), Gatrel opted to take his case to trial, defended the entire time by court-appointed attorneys.

Prosecutors said Gatrel’s booter services — downthem[.]org and ampnode[.]com — helped some 2,000 paying customers launch debilitating digital assaults on more than 20,000 targets, including many government, banking, university and gaming websites.

Gatrel was convicted on all three charges of violating the Computer Fraud and Abuse Act, including conspiracy to commit unauthorized impairment of a protected computer, conspiracy to commit wire fraud, and unauthorized impairment of a protected computer. He was sentenced to two years in prison.

Now, it appears Dobbs is also planning to take his chances with a jury. On Jan. 4, Dobbs entered a plea of not guilty. Neither Dobbs nor his court-appointed attorney responded to requests for comment.

But as it happens, Dobbs himself provided some perspective on his thinking in an email exchange with KrebsOnSecurity back in 2020. I’d reached out to Dobbs because it was obvious he didn’t mind if people knew he operated one of the world’s most popular DDoS-for-hire sites, and I was genuinely curious why he was so unafraid of getting raided by the feds.

“Yes, I am the owner of the domain you listed, however you are not authorized to post an article containing said domain name, my name or this email address without my prior written permission,” Dobbs replied to my initial outreach on March 10, 2020 using his email address from the University of Hawaii at Manoa.

A few hours later, I received more strident instructions from Dobbs, this time via his official email address at ipstresser[.]com.

“I will state again for absolute clarity, you are not authorized to post an article containing ipstresser.com, my name, my GitHub profile and/or my hawaii.edu email address,” Dobbs wrote, as if taking dictation from a lawyer who doesn’t understand how the media works.

When pressed for particulars on his business, Dobbs replied that the number of IPStresser customers was “privileged information,” and said he didn’t even advertise the service. When asked whether he was concerned that many of his competitors were by then serving jail time for operating similar booter services, Dobbs maintained that the way he’d set up the business insulated him from any liability.

“I have been aware of the recent law enforcement actions against other operators of stress testing services,” Dobbs explained. “I cannot speak to the actions of these other services, but we take proactive measures to prevent misuse of our service and we work with law enforcement agencies regarding any reported abuse of our service.”

What were those proactive measures? In a 2015 interview with ZDNet France, Dobbs asserted that he was immune from liability because his clients all had to submit a digital signature attesting that they wouldn’t use the site for illegal purposes.

“Our terms of use are a legal document that protects us, among other things, from certain legal consequences,” Dobbs told ZDNet. “Most other sites are satisfied with a simple checkbox, but we ask for a digital signature in order to imply real consent from our customers.”

Dobbs told KrebsOnSecurity his service didn’t generate much of a profit, but rather that he was motivated by “filling a legitimate need.”

“My reason for offering the service is to provide the ability to test network security measures before someone with malicious intent attacks said network and causes downtime,” he said. “Sure, some people see only the negatives, but there is a long list of companies I have worked with over the years who would say my service is a godsend and has helped them prevent tens of thousands of dollars in downtime resulting from a malicious attack.”

“I do not believe that providing such a service is illegal, assuming proper due diligence to prevent malicious use of the service, as is the case for IPstresser[.]com,” Dobbs continued. “Someone using such a service to conduct unauthorized testing is illegal in many countries, however, the legal liability is that of the user, not of the service provider.”

Dobbs’s profile on GitHub includes more of his ideas about his work, including a curious piece on “software engineering ethics.” In his January 2020 treatise “My Software Engineering Journey,” Dobbs laments that nothing in his formal education prepared him for the reality that a great deal of his work would be so tedious and repetitive (this tracks closely with a 2020 piece here called Career Choice Tip: Cybercrime is Mostly Boring).

“One area of software engineering that I think should be covered more in university classes is maintenance,” Dobbs wrote. “Projects are often worked on for at most a few months, and students do not experience the maintenance aspect of software engineering until they reach the workplace. Let’s face it, ongoing maintenance of a project is boring; there is nothing like the euphoria of completing a project you have been working on for months and releasing it to the world, but I would say that half of my professional career has been related to maintenance.” Continue reading →

Microsoft Patch Tuesday, January 2023 Edition

January 10, 2023
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Microsoft today released updates to fix nearly 100 security flaws in its Windows operating systems and other software. Highlights from the first Patch Tuesday of 2023 include a zero-day vulnerability in Windows, printer software flaws reported by the U.S. National Security Agency, and a critical Microsoft SharePoint Server bug that allows a remote, unauthenticated attacker to make an anonymous connection.

At least 11 of the patches released today are rated “Critical” by Microsoft, meaning they could be exploited by malware or malcontents to seize remote control over vulnerable Windows systems with little or no help from users.

Of particular concern for organizations running Microsoft SharePoint Server is CVE-2023-21743. This is a Critical security bypass flaw that could allow a remote, unauthenticated attacker to make an anonymous connection to a vulnerable SharePoint server. Microsoft says this flaw is “more likely to be exploited” at some point.

But patching this bug may not be as simple as deploying Microsoft updates. Dustin Childs, head of threat awareness at Trend Micro’s Zero Day Initiative, said sysadmins need to take additional measures to be fully protected from this vulnerability.

“To fully resolve this bug, you must also trigger a SharePoint upgrade action that’s also included in this update,” Childs said. “Full details on how to do this are in the bulletin. Situations like this are why people who scream ‘Just patch it!’ show they have never actually had to patch an enterprise in the real world.”

Eighty-seven of the vulnerabilities earned Redmond’s slightly less dire “Important” severity rating. That designation describes vulnerabilities “whose exploitation could result in compromise of the confidentiality, integrity, or availability of user data, or of the integrity or availability of processing resources.”

Among the more Important bugs this month is CVE-2023-21674, which is an “elevation of privilege” weakness in most supported versions of Windows that has already been abused in active attacks.

Satnam Narang, senior staff research engineer at Tenable, said although details about the flaw were not available at the time Microsoft published its advisory on Patch Tuesday, it appears this was likely chained together with a vulnerability in a Chromium-based browser such as Google Chrome or Microsoft Edge in order to break out of a browser’s sandbox and gain full system access.

“Vulnerabilities like CVE-2023-21674 are typically the work of advanced persistent threat (APT) groups as part of targeted attacks,” Narang said. “The likelihood of future widespread exploitation of an exploit chain like this is limited due to auto-update functionality used to patch browsers.” Continue reading →

Identity Thieves Bypassed Experian Security to View Credit Reports

January 9, 2023
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Identity thieves have been exploiting a glaring security weakness in the website of Experian, one of the big three consumer credit reporting bureaus. Normally, Experian requires that those seeking a copy of their credit report successfully answer several multiple choice questions about their financial history. But until the end of 2022, Experian’s website allowed anyone to bypass these questions and go straight to the consumer’s report. All that was needed was the person’s name, address, birthday and Social Security number.

The vulnerability in Experian’s website was exploitable after one applied to see their credit file via annualcreditreport.com.

In December, KrebsOnSecurity heard from Jenya Kushnir, a security researcher living in Ukraine who said he discovered the method being used by identity thieves after spending time on Telegram chat channels dedicated to the cashing out of compromised identities.

“I want to try and help to put a stop to it and make it more difficult for [ID thieves] to access, since [Experian is] not doing shit and regular people struggle,” Kushnir wrote in an email to KrebsOnSecurity explaining his motivations for reaching out. “If somehow I can make small change and help to improve this, inside myself I can feel that I did something that actually matters and helped others.”

Kushnir said the crooks learned they could trick Experian into giving them access to anyone’s credit report, just by editing the address displayed in the browser URL bar at a specific point in Experian’s identity verification process.

Following Kushnir’s instructions, I sought a copy of my credit report from Experian via annualcreditreport.com — a website that is required to provide all Americans with a free copy of their credit report from each of the three major reporting bureaus, once per year.

Annualcreditreport.com begins by asking for your name, address, SSN and birthday. After I supplied that and told Annualcreditreport.com I wanted my report from Experian, I was taken to Experian.com to complete the identity verification process.

Normally at this point, Experian’s website would present four or five multiple-guess questions, such as “Which of the following addresses have you lived at?”

Kushnir told me that when the questions page loads, you simply change the last part of the URL from “/acr/oow/” to “/acr/report,” and the site would display the consumer’s full credit report.

But when I tried to get my report from Experian via annualcreditreport.com, Experian’s website said it didn’t have enough information to validate my identity. It wouldn’t even show me the four multiple-guess questions. Experian said I had three options for a free credit report at this point: Mail a request along with identity documents, call a phone number for Experian, or upload proof of identity via the website.

But that didn’t stop Experian from showing me my full credit report after I changed the Experian URL as Kushnir had instructed — modifying the error page’s trailing URL from “/acr/OcwError” to simply “/acr/report”.

Experian’s website then immediately displayed my entire credit file.

Even though Experian said it couldn’t tell that I was actually me, it still coughed up my report. And thank goodness it did. The report contains so many errors that it’s probably going to take a good deal of effort on my part to straighten out.

Now I know why Experian has NEVER let me view my own file via their website. For example, there were four phone numbers on my Experian credit file: Only one of them was mine, and that one hasn’t been mine for ages.

I was so dumbfounded by Experian’s incompetence that I asked a close friend and trusted security source to try the method on her identity file at Experian. Sure enough, when she got to the part where Experian asked questions, changing the last part of the URL in her address bar to “/report” bypassed the questions and immediately displayed her full credit report. Her report also was replete with errors.

KrebsOnSecurity shared Kushnir’s findings with Experian on Dec. 23, 2022. On Dec. 27, 2022, Experian’s PR team acknowledged receipt of my Dec. 23 notification, but the company has so far ignored multiple requests for comment or clarification.

By the time Experian confirmed receipt of my report, the “exploit” Kushnir said he learned from the identity thieves on Telegram had been patched and no longer worked. But it remains unclear how long Experian’s website was making it so easy to access anyone’s credit report.

In response to information shared by KrebsOnSecurity, Senator Ron Wyden (D-Ore.) said he was disappointed — but not at all surprised — to hear about yet another cybersecurity lapse at Experian.

“The credit bureaus are poorly regulated, act as if they are above the law and have thumbed their noses at Congressional oversight,” Wyden said in a written statement. “Just last year, Experian ignored repeated briefing requests from my office after you revealed another cybersecurity lapse the company.”

Sen. Wyden’s quote above references a story published here in July 2022, which broke the news that identity thieves were hijacking consumer accounts at Experian.com just by signing up as them at Experian once more, supplying the target’s static, personal information (name, DoB/SSN, address) but a different email address.

From interviews with multiple victims who contacted KrebsOnSecurity after that story, it emerged that Experian’s own customer support representatives were actually telling consumers who got locked out of their Experian accounts to recreate their accounts using their personal information and a new email address. This was Experian’s advice even for people who’d just explained that this method was what identity thieves had used to lock them in out in the first place. Continue reading →