Security researchers have released a patch designed to protect users against an outstanding Internet Explorer vulnerability in the absence of available security updates from Microsoft.
A new ad-hoc group of security pros, called the Zeroday Emergency Response Team (ZERT), has released an unofficial fix designed to address the Vector Markup Language (VML) component vulnerability in IE, the most serious of two unpatched IE vulnerabilities. It plans to release other security bug fixes in future.
Hackers are taking advantage of this VML security flaw in IE to infect users visiting pornographic websites. Opening maliciously constructed emails in Outlook is also a potential risk, especially as attacks targeting the vulnerability are growing in prevalence since their first appearance last week.
The security bug is unrelated to a (still unpatched) flaw in Microsoft's Direct Animation Path (daxctle.ocx) ActiveX control discovered earlier this month.
ZERT said users should replace its fix with Microsoft's patch once this becomes available. "It is always a good idea to wait for a vendor-supplied patch and apply it as soon as possible, but there will be times when an ad-hoc group such as ours can release a working patch before a vendor can release their solution," it said.
Separately, security management firm PatchLink released a more limited workaround designed to help its customers (and only its customers) protect their networks from the VML exploit.
PatchLink estimates the number of vulnerabilities in various applications released this year will reach 6,700, some of which will become the subject of exploit before vendors get around to releasing patches.
Because of the growing issue of unpatched (so called zero-day) exploits, IT administrators can expect to see more third party patches such as the VML patch released by the ZERT group. PatchLink advises to check the provenance of patches and carry out testing before applying fixes in case they cause more problems than they solve in a user's environment. ®