Posts Tagged: zero day


23
Jun 15

Emergency Patch for Adobe Flash Zero-Day

Adobe Systems Inc. today released an emergency update to fix a dangerous security hole in its widely-installed Flash Player browser plugin. The company warned that the vulnerability is already being exploited in targeted attacks, and urged users to update the program as quickly as possible.

In an advisory issued Tuesday morning, Adobe said the latest version of Flash — v. 18.0.0.194 on Windows and Mac OS X — fixes a critical flaw (CVE-2015-3113) that is being actively exploited in “limited, targeted attacks.” The company said systems running Internet Explorer for Windows 7 and below, as well as Firefox on Windows XP, are known targets of these exploits. Continue reading →


23
Jun 15

A Month Without Adobe Flash Player

I’ve spent the better part of the last month running a little experiment to see how much I would miss Adobe‘s buggy and insecure Flash Player software if I removed it from my systems altogether. Turns out, not so much.

brokenflash-aBrowser plugins are favorite targets for malware and miscreants because they are generally full of unpatched or undocumented security holes that cybercrooks can use to seize complete control over vulnerable systems. The Flash Player plugin is a stellar example of this: It is among the most widely used browser plugins, and it requires monthly patching (if not more frequently).

It’s also not uncommon for Adobe to release emergency fixes for the software to patch flaws that bad guys started exploiting before Adobe even knew about the bugs. This happened most recently in February 2015, and twice the month prior. Adobe also shipped out-of-band Flash fixes in December and November 2014.

Update, 11:30 a.m. ET: Oddly enough, Adobe just minutes ago released an out-of-band patch to fix a zero-day flaw in Flash.

Original story:

Time was, Oracle’s Java plugin was the favorite target of exploit kits, software tools made to be stitched into hacked or malicious sites and foist on visiting browsers a kitchen sink of exploits for various plugin vulnerabilities. Lately, however, it seems to pendulum has swung back in favor of exploits for Flash Player. A popular exploit kit known as Angler, for example, bundled a new exploit for a Flash vulnerability just three days after Adobe fixed it in April 2015.

So, rather than continue the patch madness and keep this insecure software installed, I decided to the pull the…er…plugin. I tend to (ab)use different browsers for different tasks, and so uninstalling the plugin was almost as simple as uninstalling Flash, except with Chrome, which bundles its own version of Flash Player. Fear not: disabling Flash in Chrome is simple enough. On a Windows, Mac, Linux or Chrome OS installation of Chrome, type “chrome:plugins” into the address bar, and on the Plug-ins page look for the “Flash” listing: To disable Flash, click the disable link (to re-enable it, click “enable”).

In almost 30 days, I only ran into just two instances where I encountered a site hosting a video that I absolutely needed to watch and that required Flash (an instructional video for a home gym that I could find nowhere else, and a live-streamed legislative hearing). For these, I opted to cheat and load the content into a Flash-enabled browser inside of a Linux virtual machine I have running inside of VirtualBox. In hindsight, it probably would have been easier simply to temporarily re-enable Flash in Chrome, and then disable it again until the need arose. Continue reading →


27
Jan 15

Yet Another Emergency Flash Player Patch

For the second time in a week, Adobe has issued an emergency update to fix a critical security flaw that crooks are actively exploiting in its Flash Player software. Updates are available for Flash Player on Windows and Mac OS X.

brokenflash-aLast week, Adobe released an out-of-band Flash Patch to fix a dangerous bug that attackers were already exploiting. In that advisory, Adobe said it was aware of yet another zero-day flaw that also was being exploited, but that last week’s patch didn’t fix that flaw.

Earlier this week, Adobe began pushing out Flash v. 16.0.0.296 to address the outstanding zero-day flaw. Adobe said users who have enabled auto-update for Flash Player will be receiving the update automatically this week. Alternatively, users can manually update by downloading the latest version from this page.

Adobe said it is working with its distribution partners to make the update available in Google Chrome and Internet Explorer 10 and 11. Google Chrome version 40.0.2214.93 includes this update, and is available now. To check for updates in Chrome, click the stacked three bars to the right of the address bar in Chrome, and look for a listing near the bottom that says “Update Chrome.”

To see which version of Flash you have installed, check this link. Windows users who browse the Web with anything other than Internet Explorer may need to apply this patch twice, once with IE and again using the alternative browser (Firefox, Opera, e.g.).


14
Jan 14

Security Updates for Windows, Java, Flash & Reader

Adobe, Microsoft and Oracle today each issued security updates to fix serious vulnerabilities in their products. Adobe released patches for AIR, Acrobat, Flash and Reader, while Microsoft pushed out fixes to shore up at least a half dozen security weaknesses in Windows and Office. Oracle released an update for Java that fixes at least three dozen security holes in the widely-used program.

crackedwinAll of the vulnerabilities that Microsoft fixed this month earned “important” ratings; not quite as dire as those labeled “critical,” which involve flaws so dangerous that they can be exploited by bad guys or malware to break into systems with no user interaction. Nevertheless, flaws marked “important” can be quite dangerous, particularly when used in tandem with other attack techniques.

By way of illustration, this month’s MS14-002 patch addresses an important zero-day flaw that was first found to be exploited in targeted attacks late last year. In one version of this attack, documented quite nicely in this fascinating yet somewhat technical writeup from Trustwave Spiderlabs, attackers used this Windows flaw in combination with a bug in Adobe Reader. According to Trustwave, the bad guys in that attack included the Windows flaw as a means of bypassing Adobe Reader’s security sandbox, a technology designed ensure that any malicious code embedded in documents only runs under limited privileges (i.e., isn’t allowed to invoke other programs or alter core system settings).

In short, don’t put off applying this month’s patches from Microsoft. They are available via Windows Update or Automatic Update. Also, Microsoft took this opportunity to remind Windows XP users that the company will no longer be supporting Windows XP after April 2014 (guess I will have to retire the above broken Windows graphic as well). The lack of ongoing security updates for XP means it will likely become an even bigger target for attackers; if you rely on XP, please consider transitioning to a newer operating system sometime soon. Who knows, it might be a great excuse to try Linux, which tends to be very light on resources and ideal for older hardware. If you’ve been considering the switch for a while, take a few distributions for a spin using one of dozens of flavors of Linux available via Live CD.

Continue reading →


12
Nov 13

Zero-Days Rule November’s Patch Tuesday

Microsoft today issued security updates to fix at least 19 vulnerabilities in its software, including a zero-day flaw in Internet Explorer browser that is already being actively exploited. Separately, Adobe has released a critical update that plugs at least two security holes in its Flash Player software.

crackedwinThree of the eight patches that Microsoft released earned its most dire “critical” label, meaning the vulnerabilities fixed in them can be exploited by malware or miscreants remotely without any help from Windows users. Among the critical patches is an update for Internet Explorer (MS13-088) that mends at least two holes in the default Windows browser (including IE 11). MS13-089 is a critical file handling flaw present in virtually every supported version of Windows.

The final critical patch — MS13-090 — fixes essentially another IE flaw (ActiveX) that showed up in targeted attacks late last week. Microsoft says attackers used a second, “information disclosure” vulnerability in tandem with the ActiveX flaw, but that the company is still investigating that one. It noted that its Enhanced Mitigation Experience Toolkit (EMET) tool successfully blocked the ActiveX exploit.

Nevertheless, it’s important for IE users to apply these updates as quickly as possible. According to Rapid7, exploit code for the ActiveX vulnerability appeared on Pastebin this morning.

“It was known to be under some targeted exploitation, but that will probably expand now that the exploit is public,” said Ross Barrett, senior manager of security engineering at Rapid7. “I would call patching this issue priority #1.” For what it’s worth, Microsoft agrees, at least according to this suggested patch deployment chart.

Today’s patch batch from Redmond did not include an official patch for yet another zero-day vulnerability that has been under active exploitation, although Microsoft did release a stopgap Fix-It tool last week to help blunt the threat. The company also is once again advising Windows users to take another look at EMET.

Check out Microsoft’s Technet blog for more information on these and other updates that the company released today.

brokenflash-aIn a separate patch release, Adobe issued a fix for its Flash Player software for Windows, Mac, Linux and Android devices. The Flash update brings the ubiquitous player to v. 11.9.900.152 on Mac and Windows systems. Users browsing the Web with IE10 or IE11 on Windows 8.x should get the new version of Flash (11.9.900.152) automatically; IE users not on Windows 8 will need to update manually if Flash is not set to auto-update.

To check which version of Flash you have installed, visit this page. Direct links to the various Flash installers are available here. Be aware that downloading Flash Player from Adobe’s recommended spot — this page — often includes add-ons, security scanners or other crud you probably don’t want. Strangely enough, when I visited that page today with IE10 , the download included a pre-checked box to install Google Toolbar and to switch my default browser to Google Chrome.

Continue reading →


6
May 13

Zero-Day Exploit Published for IE8

Security experts are warning that a newly discovered vulnerability in Internet Explorer 8 is being actively exploited to break into Microsoft Windows systems. Complicating matters further, computer code that can be used to reliably exploit the flaw is now publicly available online.

IEwarningIn an advisory released May 3, Microsoft said it was investigating reports of a vulnerability in IE8, and that it was aware of attacks that attempt to exploit this bug. The company stresses that other versions of IE — including IE6, 7, 9 and 10 are not affected by the vulnerability. However, all versions of IE8 are vulnerable, including copies running on Windows XP, Vista and Windows 7.

Meanwhile, a new module that exploits this IE8 bug is now available for the Metasploit Framework, a free penetration testing tool. I would expect this exploit or some version of it will soon be rolled into commercial exploit kits that are sold in the cybercrime underground (assuming this has not already happened).

Update, May 9, 9:00 a.m. ET: Microsoft has released a fix-it tool to blunt attacks on this bug. See this story for more information.

Original post:

The security hole has already been leveraged in at least one high-profile attack. Over the weekend, several security vendors reported that the U.S. Department of Labor Web site had been hacked and seeded with code designed to exploit the flaw and download malicious software.

The attack on the Labor Department site is seen as a watering hole attack, which involves the targeted compromise of legitimate websites thought to be of interest to or frequented by end users who belong to organizations that attackers wish to infiltrate. Previous watering hole attacks have targeted the Web site for the Council on Foreign Relations, the Association of Southeast Asian Nations, and the National Democratic Institute.

According to CrowdStrike, the server used to control this latest attack on the Labor Department site was microsoftupdate.ns1.name. The company said analysis of the logs from the attacker’s infrastructure revealed that visitors from 37 different countries browsed the site during the time it was compromised with the malicious code. AlienVault, Invincea and Cisco Systems have published additional details on this attack. AlienVault also said it has since spotted the same exploit used on at least nine other hacked Web sites, including several non-profit groups and a large European company.

Continue reading →


2
Apr 13

Fool Me Once…

When you’re lurking in the computer crime underground, it pays to watch your back and to keep your BS meter set to  ‘maximum.’ But when you’ve gained access to an elite black market section of a closely guarded crime forum to which very few have access, it’s easy to let your guard down. That’s what I did earlier this year, and it caused me to chase a false story. This blog post aims to set the record straight on that front, and to offer a cautionary (and possibly entertaining) tale to other would-be cybersleuths.

baitOn Jan. 16, 2013, I published a post titled, “New Java Exploit Fetches $5,000 Per Buyer.” The details in that story came from a sales thread posted to an exclusive subforum of Darkode.com, a secretive underground community that has long served as a bazaar for all manner of cybercriminal wares, including exploit kitsspam services, ransomware programs, and stealthy botnets. I’ve maintained a presence on this forum off and on (mostly on) for the past three years, in large part because Darkode has been a reliable place to find information about zero-days, or highly valuable threats that exploit previously unknown vulnerabilities in software — threats that are shared or used by attackers before the developer of the target software knows about the vulnerability.

I had previously broken several other stories about zero-day exploits for sale on Darkode that later showed up “in-the-wild” and confirmed by the affected vendors, and this sales thread was posted by one of the forum’s most trusted members. The sales thread also was created during a time in which Java’s maker Oracle Corp. was struggling with multiple zero-days in Java.

What I didn’t know at the time was that this particular sales thread was little more than a carefully laid trap by the Darkode administrators to discover which accounts I was using to lurk on their forum. Ironically, I recently learned of this snare after white/grey hat hackers compromised virtually all of the administrator accounts and private messages on Darkode.

“Looks like Krebs swallowed the bait, and i got an idea how to catch him now for the next thread,” wrote Darkode administrator “Mafi” in a Jan. 16 private message to a co-admin who uses the nickname “sp3cial1st”.

Following this post, the administrators compared notes as to which users had viewed the fake Java zero-day sales thread during the brief, two-day period it was live on a restricted portion of Darkode. “I have taken a careful examination of the logs related to the java 0day thread,” sp3cial1st wrote to a Darkode administrator who used the nick “187”.

Continue reading →


27
Feb 13

Flash Player Update Fixes Zero-Day Flaws

Adobe has released an emergency update for its Flash Player software that fixes three critical vulnerabilities, two of which the company warns are actively being exploited to compromise systems.

brokenflash-aIn an advisory, Adobe said two of the bugs quashed in this update (CVE-2013-0643 and CVE-2013-0648) are being used by attackers to target Firefox users. The company noted that the attacks are designed to trick users into clicking a link which redirects to a Web site serving malicious Flash content.

Readers can be forgiven for feeling patch fatigue with Flash: This is the third security update that Adobe has shipped for Flash in the last month. On Feb. 12, Adobe released a patch to plug at least 17 security holes in Flash. On Feb. 7, Adobe rushed out an update to fix two other flaws that attackers were already exploiting to break into vulnerable computers.

Continue reading →


20
Feb 13

Critical Security Updates for Adobe Reader, Java

Adobe and Oracle each released updates to fix critical security holes in their software. Adobe’s patch plugs two zero-day holes that hackers have been using to break into computers via Adobe Reader and Acrobat. Separately, Oracle issued updates to correct at least five security issues with Java.

javaiconThe Java update comes amid revelations by Apple, Facebook and Twitter that employees at these organizations were hacked using exploits that attacked Java vulnerabilities on Mac and Windows machines. According to Bloomberg News, at least 40 companies were targeted in malware attacks linked to an Eastern European gang of hackers that has been trying to steal corporate secrets.

Oracle’s update brings Java on Windows systems to Java SE 7 Update 15, and Java 6 Update 41. Most consumers can get by without Java installed, or least not plugged into the browser. Because of the prevalence of threats targeting Java installations, I’d urge these users to remove Java or unplug it from the browser. If this is too much trouble, consider adopting a dual-browser approach, keeping Java unplugged from your main browser, and plugged in to a secondary browser that you only use to visit sites that require the plugin. To find out if you have Java installed, visit java.com and click the “Do I have Java?” link below the big red button. Existing users can update Java from the Java Control Panel, clicking the Update tab and then the “Update Now” button.

Apple has issued an update that brings Java up-to-date on security patches but also disables the Java plugin from Web browsers on the system. Apple also issued a malware removal tool that it said should remove from Macs the most common variants of malware that used the most recent Java exploits. Continue reading →


7
Feb 13

Critical Flash Player Update Fixes 2 Zero-Days

Adobe today pushed out an emergency update that fixes at least two zero-day vulnerabilities in its ubiquitous Flash Player software — flaws that attackers are already exploiting to break into systems. Interestingly, Adobe warns that one of the exploits in use is designed to drop malware on both Windows and Mac OS X systems.

brokenflash-aAdobe said in an advisory that one of the vulnerabilities — CVE-2013-0634 – is being exploited in the wild in attacks delivered via malicious Flash content hosted on websites that target Flash Player in Firefox or Safari on the Macintosh platform, as well as attacks designed to trick Windows users into opening a Microsoft Word document delivered as an email attachment.

Adobe also warned that a separate flaw — CVE-2013-0633 — is being exploited in the wild in targeted attacks designed to trick the user into opening a Microsoft Word document delivered as an email attachment which contains malicious Flash content. The company said the exploit for CVE-2013-0633 targets the ActiveX version of Flash Player on Windows (i.e. Internet Explorer users).

Updates are available for Windows, Mac, Linux and Android users. The latest Windows and Mac version is v. 11.5.502.149, and is available from this link. Those who prefer a direct link to the OS-specific downloads can grab them here. To find out if you have Flash installed and what version your browser may be running, check out this page.

flash115502149

Flash Player installed with Google Chrome should automatically be updated to the latest Google Chrome version, which will include Adobe Flash Player v. 11.5.31.139 for Windows, Macintosh and Linux. Likewise, Internet Explorer 10 for Windows 8 also includes an auto-update feature, which should bring Flash to version 11.3.379.14 for Windows.

Adobe’s advisory notes that the vulnerability that has been used to attack both Mac and Windows users was reported with the help of the Shadowserver Foundation, the federally funded technology research center MITRE Corporation, and aerospace giant Lockheed Martin‘s computer incident response team. No doubt there are some interesting stories about how these attacks were first discovered, and against whom they were initially deployed.