Microsoft's November Patch Tuesday will not include a fix for a zero day vulnerability in its Office service being actively targeted by cyber criminals, the firm has disclosed.
Microsoft confirmed that its latest patch Tuesday fixes will address eight other security vulnerabilities. Rapid7 Security Engineering senior manager Ross Barrett explained that the fixes relate to separate issues in Microsoft Office as well as vulnerabilities in Internet Explorer and Windows.
"This is a relatively straightforward Patch Tuesday, with fixes for most Windows versions, the ever-present Internet Explorer roll-up patch, and some Office components, but nothing esoteric or difficult to patch. No SharePoint plugins, no complicated .NET patching, no esoteric office extensions," he said.
The flaw in Office was revealed earlier this week and Microsoft has confirmed that the vulnerability is being actively exploited by hackers. Security firms FireEye and Symantec have since traced the attacks to the Operation Hangover group of hackers. Operation Hangover is an espionage-focused hacking campaign that was uncovered in May.
Microsoft has released a workaround fix for the Office vulnerability but has yet to confirm when it will release a complete patch. Director of Security Research at Trustwave Ziv Mador said the critical nature of the Office vulnerability means Microsoft is likely to deliver a full fix in its December Patch Tuesday release.
"Microsoft has warned of a zero-day attack being actively exploited in the wild and directed against users of Microsoft Office. Microsoft has already released a ‘Fix it' tool to help remediate this vulnerability but we will probably have to wait until next month for a full patch. The issues centre around how some components of Microsoft Office render Tiff files and can result in remote code execution," he said.
The latest Patch Tuesday updates are due for release on 12 November. Patch Tuesday is a part of Microsoft's wider efforts to improve its product security.
As well as the monthly security fixes, Microsoft also actively encourages security researchers to alert it of flaws in its services using bug bounty reward programmes. Microsoft expanded its bug bounty reward programme to reward researchers for alerts about active cyber attacks on its services as well as theoretical exploits earlier in November.