November's edition of Patch Tuesday brought relief from an IE zero-day exploit but a TIFF image-handling vulnerability under active attack from hackers remains unpatched.
Microsoft released a total of five bulletins, three of which are marked up as critical and five of which are designated as important. The patch batch collectively addresses 19 vulnerabilities in Windows and Office software.
MS13-088 fixes 10 vulnerabilities in all supported versions of Internet Explorer (IE 6, 7, 8, 9, 10 and 11). The second of the critical updates (MS13-089) tackles a flaw in the Microsoft Windows Graphics Device Interface (GDI) that create a means to inject malware onto vulnerable systems after tricking a user into opening a document loaded with malicious code. Every supported version of Windows is affected.
The final critical patch guards against an attack first disclosed by security firm FireEye last week. As it turns out, Microsoft was already aware of the Internet Explorer ActiveX Control-related flaw and had created and tested the fix. This is just as well because Symantec has linked abuse of the vulnerability to the notorious Hidden Lynx hacking crew, a group of "hackers for hire" based in China suspected of running APT-style attacks against targets in the US, Taiwan and elsewhere since 2009.
The remaining five bulletins deal with lesser "important" flaws in Microsoft's software, the most noteworthy of which grapples with a denial of service vulnerability in the software giant's virtualisation product, Hyper-V.
Wolfgang Kandek, CTO at cloud security firm Qualys, commented: "Overall, while it is only a medium-sized Patch Tuesday, pay special attention to the two 0-days and the Internet Explorer update. Browsers continue to be the favourite target for attackers, and Internet Explorer, with its leading market share, is one of the most visible and likely targets."
The release confirms, as expected, that there's no immediate relief for a separate zero-day vulnerability involving how Office handles .TIFF graphics files. The CVE-2013-3906 flaw is being actively exploited in attacks, typically featuring booby-trapped Word files, by an increasing numbers of both profit-motivated cybercrooks and cyberspying groups. Microsoft has issued a workaround involving disabling the vulnerable graphics library that is increasingly become a must-have accessory for corporate networks.
The unpatched bug affects Microsoft Office 2003 and 2007. Office 2010 is also affected but only when the suite runs on older versions of Windows such as Windows XP or Windows Server 2003.
In other patching news, Adobe released updates for Flash Player, Air and ColdFusion. The Flash Player update is designed to resolve two critical vulnerabilities, while the ColdFusion update fixes one.
ColdFusion was among the platforms whose source code was leaked last month during a major breach of Adobe's systems that led to the loss of 150 million user account credentials.
As previously reported, Adobe said that Tuesday's update addresses a different set of security risks which have yet to be targeted by attackers in the wild. The software firm credits Hold Security for research that helps uncover bugs that needed patching.
Hold Security linked attacks against ColdFusion version 8 to the recent high profile theft of Adobe source code as well as attacks against LexisNexis and others.
"While Adobe did not find the precise attack effective against any of supported CF versions, they did identify a critical flaw in the same resource which led to the patch issued today [Tuesday]," Alex Holden of Hold Security told KrebsOnSecurity.
Finally Google released a new version of its browser (Chrome 31) that features 25 security fixes and other tweaks, including improvement to SSL ciphers that come with the addition of support for the AES-GCM ciphers. ®