Posts Tagged: Microsoft Windows


8
Feb 20

Dangerous Domain Corp.com Goes Up for Sale

As an early domain name investor, Mike O’Connor had by 1994 snatched up several choice online destinations, including bar.com, cafes.com, grill.com, place.com, pub.com and television.com. Some he sold over the years, but for the past 26 years O’Connor refused to auction perhaps the most sensitive domain in his stable — corp.com. It is sensitive because years of testing shows whoever wields it would have access to an unending stream of passwords, email and other proprietary data belonging to hundreds of thousands of systems at major companies around the globe.

Now, facing 70 and seeking to simplify his estate, O’Connor is finally selling corp.com. The asking price — $1.7 million — is hardly outlandish for a 4-letter domain with such strong commercial appeal. O’Connor said he hopes Microsoft Corp. will buy it, but fears they won’t and instead it will get snatched up by someone working with organized cybercriminals or state-funded hacking groups bent on undermining the interests of Western corporations.

One reason O’Connor hopes Microsoft will buy it is that by virtue of the unique way Windows handles resolving domain names on a local network, virtually all of the computers trying to share sensitive data with corp.com are somewhat confused Windows PCs. More importantly, early versions of Windows actually encouraged the adoption of insecure settings that made it more likely Windows computers might try to share sensitive data with corp.com.

At issue is a problem known as “namespace collision,” a situation where domain names intended to be used exclusively on an internal company network end up overlapping with domains that can resolve normally on the open Internet.

Windows computers on an internal corporate network validate other things on that network using a Microsoft innovation called Active Directory, which is the umbrella term for a broad range of identity-related services in Windows environments. A core part of the way these things find each other involves a Windows feature called “DNS name devolution,” which is a kind of network shorthand that makes it easier to find other computers or servers without having to specify a full, legitimate domain name for those resources.

For instance, if a company runs an internal network with the name internalnetwork.example.com, and an employee on that network wishes to access a shared drive called “drive1,” there’s no need to type “drive1.internalnetwork.example.com” into Windows Explorer; typing “\\drive1\” alone will suffice, and Windows takes care of the rest.

But things can get far trickier with an internal Windows domain that does not map back to a second-level domain the organization actually owns and controls. And unfortunately, in early versions of Windows that supported Active Directory — Windows 2000 Server, for example — the default or example Active Directory path was given as “corp,” and many companies apparently adopted this setting without modifying it to include a domain they controlled.

Compounding things further, some companies then went on to build (and/or assimilate) vast networks of networks on top of this erroneous setting.

Now, none of this was much of a security concern back in the day when it was impractical for employees to lug their bulky desktop computers and monitors outside of the corporate network. But what happens when an employee working at a company with an Active Directory network path called “corp” takes a company laptop to the local Starbucks?

Chances are good that at least some resources on the employee’s laptop will still try to access that internal “corp” domain. And because of the way DNS name devolution works on Windows, that company laptop online via the Starbucks wireless connection is likely to then seek those same resources at “corp.com.”

In practical terms, this means that whoever controls corp.com can passively intercept private communications from hundreds of thousands of computers that end up being taken outside of a corporate environment which uses this “corp” designation for its Active Directory domain.

INSTANT CORPORATE BOTNET, ANYONE?

That’s according to Jeff Schmidt, a security expert who conducted a lengthy study on DNS namespace collisions funded in part by grants from the U.S. Department of Homeland Security. As part of that analysis, Schmidt convinced O’Connor to hold off selling corp.com so he and others could better understand and document the volume and types of traffic flowing to it each day.

During an eight month analysis of wayward internal corporate traffic destined for corp.com in 2019, Schmidt found more than 375,000 Windows PCs were trying to send this domain information it had no business receiving — including attempts to log in to internal corporate networks and access specific file shares on those networks.

For a brief period during that testing, Schmidt’s company JAS Global Advisors accepted connections at corp.com that mimicked the way local Windows networks handle logins and file-sharing attempts.

“It was terrifying,” Schmidt said. “We discontinued the experiment after 15 minutes and destroyed the data. A well-known offensive tester that consulted with JAS on this remarked that during the experiment it was ‘raining credentials’ and that he’d never seen anything like it.”

Likewise, JAS temporarily configured corp.com to accept incoming email.

“After about an hour we received in excess of 12 million emails and discontinued the experiment,” Schmidt said. “While the vast majority of the emails were of an automated nature, we found some of the emails to be sensitive and thus destroyed the entire corpus without further analysis.”

Schmidt said he and others concluded that whoever ends up controlling corp.com could have an instant botnet of well-connected enterprise machines.

“Hundreds of thousands of machines directly exploitable and countless more exploitable via lateral movement once in the enterprise,” he said. “Want an instant foothold into about 30 of the world’s largest companies according to the Forbes Global 2000? Control corp.com.” Continue reading →


3
Jun 19

Report: No ‘Eternal Blue’ Exploit Found in Baltimore City Ransomware

For almost the past month, key computer systems serving the government of Baltimore, Md. have been held hostage by a ransomware strain known as “Robbinhood.” Media publications have cited sources saying the Robbinhood version that hit Baltimore city computers was powered by “Eternal Blue,” a hacking tool developed by the U.S. National Security Agency (NSA) and leaked online in 2017. But new analysis suggests that while Eternal Blue could have been used to spread the infection, the Robbinhood malware itself contains no traces of it.

On May 25, The New York Times cited unnamed security experts briefed on the attack who blamed the ransomware’s spread on the Eternal Blue exploit, which was linked to the global WannaCry ransomware outbreak in May 2017.

That story prompted a denial from the NSA that Eternal Blue was somehow used in the Baltimore attack. It also moved Baltimore City Council President Brandon Scott to write the Maryland governor asking for federal disaster assistance and reimbursement as a result.

But according to Joe Stewart, a seasoned malware analyst now consulting with security firm Armor, the malicious software used in the Baltimore attack does not contain any Eternal Blue exploit code. Stewart said he obtained a sample of the malware that he was able to confirm was connected to the Baltimore incident.

“We took a look at it and found a pretty vanilla ransomware binary,” Stewart said. “It doesn’t even have any means of spreading across networks on its own.”

Stewart said while it’s still possible that the Eternal Blue exploit was somehow used to propagate the Robbinhood ransomware, it’s not terribly likely. Stewart said in a typical breach that leads to a ransomware outbreak, the intruders will attempt to leverage a single infection and use it as a jumping-off point to compromise critical systems on the breached network that would allow the malware to be installed on a large number of systems simultaneously.

“It certainly wouldn’t be the go-to exploit if your objective was to identify critical systems and then only when you’re ready launch the attack so you can do it all at once,” Stewart said. “At this point, Eternal Blue is probably going to be detected by internal [security] systems, or the target might already be patched for it.”

It is not known who is behind the Baltimore ransomware attack, but Armor said it was confident that the bad actor(s) in this case were the same individual(s) using the now-suspended twitter account @Robihkjn (Robbinhood). Until it was suspended at around 3:00 p.m. ET today (June 3), the @Robihkjn account had been taunting the mayor of Baltimore and city council members, who have refused to pay the ransom demand of 13 bitcoin — approximately $100,000.

In several of those tweets, the Twitter account could be seen posting links to documents allegedly stolen from Baltimore city government systems, ostensibly to both prove that those behind the Twitter account were responsible for the attack, and possibly to suggest what may happen to more of those documents if the city refuses to pay up by the payment deadline set by the extortionists — currently June 7, 2019 (the attackers postponed that deadline once already).

Some of @robihkjn’s tweets taunting Baltimore city leaders over non-payment of the $100,000 ransomware demand. The tweets included links to images of documents allegedly stolen by the intruders.

Over the past few days, however, the tweets from @Robinhkjn have grown more frequent and profanity-laced, directed at Baltimore’s leaders. The account also began tagging dozens of reporters and news organizations on Twitter.

Stewart said the @Robinhkjn Twitter account may be part of an ongoing campaign by the attackers to promote their own Robbinhood ransomware-as-a-service offering. According to Armor’s analysis, Robbinhood comes with multiple HTML templates that can be used to substitute different variables of the ransom demand, such as the ransom amount and the .onion address that victims can use to negotiate with the extortionists or pay a ransom demand. Continue reading →


15
Aug 18

Patch Tuesday, August 2018 Edition

Adobe and Microsoft each released security updates for their software on Tuesday. Adobe plugged five security holes in its Flash Player browser plugin. Microsoft pushed 17 updates to fix at least 60 vulnerabilities in Windows and other software, including two “zero-day” flaws that attackers were already exploiting before Microsoft issued patches to fix them.

According to security firm Ivanti, the first of the two zero-day flaws (CVE-2018-8373) is a critical flaw in Internet Explorer that attackers could use to foist malware on IE users who browse to hacked or booby-trapped sites. The other zero-day is a bug (CVE-2018-8414) in the Windows 10 shell that could allow an attacker to run code of his choice.

Microsoft also patched more variants of the Meltdown/Spectre memory vulnerabilities, collectively dubbed “Foreshadow” by a team of researchers who discovered and reported the Intel-based flaws. For more information about how Foreshadow works, check out their academic paper (PDF), and/or the video below. Microsoft’s analysis is here.

One nifty little bug fixed in this patch batch is CVE-2018-8345. It addresses a problem in the way Windows handles shortcut files; ending in the “.lnk” extension, shortcut files are Windows components that link (hence the “lnk” extension) easy-to-recognize icons to specific executable programs, and are typically placed on the user’s Desktop or Start Menu.

That description of a shortcut file was taken verbatim from the first widely read report on what would later be dubbed the Stuxnet worm, which also employed an exploit for a weakness in the way Windows handled shortcut (.lnk) files. According to security firm Qualys, this patch should be prioritized for both workstations and servers, as the user does not need to click the file to exploit. “Simply viewing a malicious LNK file can execute code as the logged-in user,” Qualys’ Jimmy Graham wrote. Continue reading →


13
Feb 18

Microsoft Patch Tuesday, February 2018 Edition

Microsoft today released a bevy of security updates to tackle more than 50 serious weaknesses in Windows, Internet Explorer/Edge, Microsoft Office and Adobe Flash Player, among other products. A good number of the patches issued today ship with Microsoft’s “critical” rating, meaning the problems they fix could be exploited remotely by miscreants or malware to seize complete control over vulnerable systems — with little or no help from users.

February’s Patch Tuesday batch includes fixes for at least 55 security holes. Some of the scarier bugs include vulnerabilities in Microsoft Outlook, Edge and Office that could let bad guys or bad code into your Windows system just by getting you to click on a booby trapped link, document or visit a compromised/hacked Web page.

As per usual, the SANS Internet Storm Center has a handy rundown on the individual flaws, neatly indexing them by severity rating, exploitability and whether the problems have been publicly disclosed or exploited. Continue reading →


27
Jun 17

‘Petya’ Ransomware Outbreak Goes Global

A new strain of ransomware dubbed “Petya” is worming its way around the world with alarming speed. The malware is spreading using a vulnerability in Microsoft Windows that the software giant patched in March 2017 — the same bug that was exploited by the recent and prolific WannaCry ransomware strain.

The ransom note that gets displayed on screens of Microsoft Windows computers infected with Petya.

The ransom note that gets displayed on screens of Microsoft Windows computers infected with Petya.

According to multiple news reports, Ukraine appears to be among the hardest hit by Petya. The country’s government, some domestic banks and largest power companies all warned today that they were dealing with fallout from Petya infections.

Danish transport and energy firm Maersk said in a statement on its Web site that “We can confirm that Maersk IT systems are down across multiple sites and business units due to a cyber attack.” In addition, Russian energy giant Rosneft said on Twitter that it was facing a “powerful hacker attack.” However, neither company referenced ransomware or Petya.

Security firm Symantec confirmed that Petya uses the “Eternal Blue” exploit, a digital weapon that was believed to have been developed by the U.S. National Security Agency and in April 2017 leaked online by a hacker group calling itself the Shadow Brokers.

Microsoft released a patch for the Eternal Blue exploit in March (MS17-010), but many businesses put off installing the fix. Many of those that procrastinated were hit with the WannaCry ransomware attacks in May. U.S. intelligence agencies assess with medium confidence that WannaCry was the work of North Korean hackers.

Organizations and individuals who have not yet applied the Windows update for the Eternal Blue exploit should patch now. However, there are indications that Petya may have other tricks up its sleeve to spread inside of large networks. Continue reading →


14
Dec 16

New Critical Fixes for Flash, MS Windows

Both Adobe and Microsoft on Tuesday issued patches to plug critical security holes in their products. Adobe’s Flash Player patch addresses 17 security flaws, including one “zero-day” bug that is already actively being exploited by attackers. Microsoft’s bundle of updates tackles at least 42 security weaknesses in Windows and associated software.

brokenwindows

Half of the dozen patches Microsoft released yesterday earned its “critical” rating, meaning the flaws fixed in the updates could be exploited by malware or miscreants to seize remote control over vulnerable Windows computers without any help from users.

As per usual, the largest share of flaws fixed are in Microsoft’s browsers — Internet Explorer and Edge. Also included in the mix are updates for Microsoft Office and .NET.

According to security firm Shavlik, several of the vulnerabilities fixed with this Microsoft patches were publicly disclosed prior to this week, meaning would-be attackers have had a head start trying to figure out how to exploit them.

As part of a new Microsoft policy that took effect in October, home and business Windows users will no longer be able to pick and choose which updates to install and which to leave for another time. Consumers on Windows 7 Service Pack 1 and Windows 8.1 will henceforth receive what Redmond is calling a “Monthly Rollup,” which addresses both security issues and reliability issues in a single update. The “Security-only updates” option — intended for enterprises and not available via Windows Update —  will only include new security patches that are released for that month. What this means is that if any part of the patch bundle breaks, the only option is to remove the entire bundle (instead of the offending patch, as was previously possible). Continue reading →


10
Jun 15

Adobe, Microsoft Issue Critical Security Fixes

Adobe today released software updates to plug at least 13 security holes in its Flash Player software. Separately, Microsoft pushed out fixes for at least three dozen flaws in Windows and associated software.

brokenwindowsThe bulk of the flaws Microsoft addressed today (23 of them) reside in the Internet Explorer Web browser. Microsoft also issued fixes for serious problems in Office, the Windows OS itself and Windows Media Player, among other components. A link to an index of the individual Microsoft updates released today is here.

As it normally does on Patch Tuesday, Adobe issued fixes for its Flash and AIR software, plugging a slew of dangerous flaws in both products. Flash continues to be one of the more complex programs to manage and update on a computer, mainly because its auto-update function tends to lag the actual patches by several days at least (your mileage may vary), and it’s difficult to know which version is the latest. Continue reading →


12
Mar 15

MS Update 3033929 Causing Reboot Loop

One of the operating system updates Microsoft released on Tuesday of this week — KB3033929 — is causing a reboot loop for a fair number of Windows 7 users, according to postings on multiple help forums. The update in question does not appear to address a pressing security vulnerability, so users who have not  yet installed it should probably delay doing so until Microsoft straightens things out. Continue reading →


10
Feb 15

Microsoft Pushes Patches for Dozens of Flaws

Microsoft today released nine update bundles to plug at least 55 distinct security vulnerabilities in its Windows operating system and other software. Three of the patches fix bugs in Windows that Microsoft considers “critical,” meaning they can be exploited remotely to compromise vulnerable systems with little or no help from users, save for perhaps clicking a link or visiting a hostile Web site.

brokenwindowsThe bulk of the flaws (41) addressed in this update apply to Internet Explorer, the default browser on Windows. This patch should obviously be a priority for any organizations that rely on IE. Other patches fix bugs in the Windows OS itself and in various versions of Microsoft Office. A full breakdown of the patches is available here.

Among the more interesting critical patches is a fix for a vulnerability in Microsoft Group Policy that could present unique threats for enterprises that rely on Active Directory, the default authentication mechanism on corporate Windows networks.  The vulnerability is remotely exploitable and can be used to grant attackers administrator-level privileges on the targeted machine or device –  that means 10s of millions of PCS, kiosks and other devices, if left untreated.

Several readers who’ve already applied these updates report that doing so may require multiple restarts of Windows. Patches are available via Windows Update, the patching mechanism built into all recent and supported versions of Windows. For more granular information about these patches, check out this blog post by Qualys as well as the always-useful roundup at the SANS Internet Storm Center.

As always, if you experience any issues applying these patches or after applying them, please leave a note in the comments section below describing your experience.


9
Sep 14

Critical Fixes for Adobe, Microsoft Software

Adobe today released updates to fix at least a dozen critical security problems in its Flash Player and AIR software. Separately, Microsoft pushed four update bundles to address at least 42 vulnerabilities in Windows, Internet Explorer, Lync and .NET Framework. If you use any of these, it’s time to update! Continue reading →