Feeds

MS kernel patch skirts infected machines

Damage control bypasses pwned PCs

Security for virtualized datacentres

Microsoft's latest batch of patches contains a kernel update designed not to install on machines infected with a rootkit.

The move is designed to prevent the confusion that occurred when one of the patches released in February resulted in a Blue Screen of Death and continuous reboot cycles on some Windows XP machines.

Microsoft copped a fair bit of criticism for the incident before the cause was pinned down to the interaction between the hard-to-detect Tdss rootkit and a Windows kernel security update. Rootkits are a type of malware that attempt to avoid detection by anti-virus scanners by burying themselves in the likes of Windows kernel code.

Redmond's April patch batch also contains a Windows kernel patch. In an effort to prevent the same snafu as February, Microsoft is using technology designed to prevent the update from installing onto malware-compromised machines.

"This security update includes package-detection logic that prevents the installation of the security update if certain abnormal conditions exist" Microsoft explains in the FAQ for its MS10-21 patch.

"These abnormal conditions on a system could be the result of an infection with a computer virus that modifies some operating system files, which renders the infected computer incompatible with the kernel update."

The same technology was used in a modified version of the MS10-15 update, which was initially released as part of February's Patch Tuesday and revised with an "avoid infected systems" add-on in mid-March.

Users who attempt to install either the revised MS010-15 package or the new Ms10-021 kernel update on infected machines ought to get an error code.

Possible error codes (such as 0x8007F0F4) fail to explain what might have gone wrong, but a bit of judicious searching ought to direct sys admins or regular users who hit the snag to this advisory here. This notice explains that users who run across problems installing the patch are probably dealing with a malware-infected machine.

Microsoft's April patch batch included 11 bulletins along with an update to the software giant's Malicious Software Removal Tool. The idea is that this tool will remove malware and clean up systems which can then by safely patched at the second time of asking. ®

Secure remote control for conventional and virtual desktops

More from The Register

next story
NASTY SSL 3.0 vuln to be revealed soon – sources (Update: It's POODLE)
So nasty no one's even whispering until patch is out
Russian hackers exploit 'Sandworm' bug 'to spy on NATO, EU PCs'
Fix imminent from Microsoft for Vista, Server 2008, other stuff
'LulzSec leader Aush0k' found to be naughty boy not worthy of jail
15 months home detention leaves egg on feds' faces as they grab for more power
Forget passwords, let's use SELFIES, says Obama's cyber tsar
Michael Daniel wants to kill passwords dead
FBI boss: We don't want a backdoor, we want the front door to phones
Claims it's what the Founding Fathers would have wanted – catching killers and pedos
Kill off SSL 3.0 NOW: HTTPS savaged by vicious POODLE
Pull it out ASAP, it is SWISS CHEESE
Facebook slurps 'paste sites' for STOLEN passwords, sprinkles on hash and salt
Zuck's ad empire DOESN'T see details in plain text. Phew!
prev story

Whitepapers

Forging a new future with identity relationship management
Learn about ForgeRock's next generation IRM platform and how it is designed to empower CEOS's and enterprises to engage with consumers.
Why cloud backup?
Combining the latest advancements in disk-based backup with secure, integrated, cloud technologies offer organizations fast and assured recovery of their critical enterprise data.
Win a year’s supply of chocolate
There is no techie angle to this competition so we're not going to pretend there is, but everyone loves chocolate so who cares.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Intelligent flash storage arrays
Tegile Intelligent Storage Arrays with IntelliFlash helps IT boost storage utilization and effciency while delivering unmatched storage savings and performance.