March 25, 2023

Microsoft in the present day launched updates to repair practically 100 safety flaws in its Home windows working programs and different software program. Highlights from the primary Patch Tuesday of 2023 embrace a zero-day vulnerability in Home windows, printer software program flaws reported by the U.S. Nationwide Safety Company, and a vital Microsoft SharePoint Server bug that permits a distant, unauthenticated attacker to make an nameless connection.

Not less than 11 of the patches launched in the present day are rated “Vital” by Microsoft, which means they could possibly be exploited by malware or malcontents to grab distant management over weak Home windows programs with little or no assist from customers.

Of specific concern for organizations working Microsoft SharePoint Server is CVE-2023-21743. This can be a Vital safety bypass flaw that would enable a distant, unauthenticated attacker to make an nameless connection to a weak SharePoint server. Microsoft says this flaw is “extra more likely to be exploited” sooner or later.

However patching this bug is probably not so simple as deploying Microsoft updates. Dustin Childs, head of menace consciousness at Pattern Micro’s Zero Day Initiative, stated sysadmins must take extra measures to be absolutely protected against this vulnerability.

“To totally resolve this bug, you should additionally set off a SharePoint improve motion that’s additionally included on this replace,” Childs stated. “Full particulars on how to do that are within the bulletin. Conditions like this are why individuals who scream ‘Simply patch it!’ present they’ve by no means really needed to patch an enterprise in the true world.”

Eighty-seven of the vulnerabilities earned Redmond’s barely much less dire “Essential” severity ranking. That designation describes vulnerabilities “whose exploitation might lead to compromise of the confidentiality, integrity, or availability of consumer knowledge, or of the integrity or availability of processing sources.”

Among the many extra Essential bugs this month is CVE-2023-21674, which is an “elevation of privilege” weak point in most supported variations of Home windows that has already been abused in lively assaults.

Satnam Narang, senior workers analysis engineer at Tenable, stated though particulars in regards to the flaw weren’t obtainable on the time Microsoft revealed its advisory on Patch Tuesday, it seems this was doubtless chained along with a vulnerability in a Chromium-based browser akin to Google Chrome or Microsoft Edge to be able to escape of a browser’s sandbox and acquire full system entry.

“Vulnerabilities like CVE-2023-21674 are usually the work of superior persistent menace (APT) teams as a part of focused assaults,” Narang stated. “The probability of future widespread exploitation of an exploit chain like that is restricted as a result of auto-update performance used to patch browsers.”

By the way in which, when was the final time you fully closed out your Internet browser and restarted it? Some browsers will robotically obtain and set up new safety updates, however the safety from these updates often solely occurs after you restart the browser.

Talking of APT teams, the U.S. Nationwide Safety Company is credited with reporting CVE-2023-21678, which is one other “vital” vulnerability within the Home windows Print Spooler software program.

There have been so many vulnerabilities patched in Microsoft’s printing software program over the previous yr (together with the dastardly PrintNightmare assaults and borked patches) that KrebsOnSecurity has joked about Patch Tuesday experiences being sponsored by Print Spooler. Tenable’s Narang factors out that that is the third Print Spooler flaw the NSA has reported within the final yr.

Kevin Breen at Immersive Labs referred to as particular consideration to CVE-2023-21563, which is a safety function bypass in BitLocker, the info and disk encryption know-how constructed into enterprise variations of Home windows.

“For organizations which have distant customers, or customers that journey, this vulnerability could also be of curiosity,” Breen stated. “We depend on BitLocker and full-disk encryption instruments to maintain our recordsdata and knowledge secure within the occasion a laptop computer or system is stolen. Whereas data is mild, this seems to recommend that it could possibly be doable for an attacker to bypass this safety and acquire entry to the underlying working system and its contents. If safety groups usually are not capable of apply this patch, one potential mitigation could possibly be to make sure Distant System Administration is deployed with the flexibility to remotely disable and wipe property.”

There are additionally two Microsoft Trade vulnerabilities patched this month — CVE-2023-21762 and CVE-2023-21745. Given the rapidity with which menace actors exploit new Trade bugs to steal company e mail and infiltrate weak programs, organizations utilizing Trade ought to patch instantly. Microsoft’s advisory says these Trade flaws are certainly “extra more likely to be exploited.”

Adobe launched 4 patches addressing 29 flaws in Adobe Acrobat and Reader, InDesign, InCopy, and Adobe Dimension. The replace for Reader fixes 15 bugs with eight of those being ranked Vital in severity (permitting arbitrary code execution if an affected system opened a specifically crafted file).

For a extra granular rundown on the updates launched in the present day, see the SANS Internet Storm Center roundup. Practically 100 updates is quite a bit, and there are sure to be a couple of patches that trigger issues for organizations and finish customers. When that occurs, often has the lowdown.

Please contemplate backing up your knowledge and/or imaging your system earlier than making use of any updates. And please pontificate within the feedback in case you expertise any issues on account of these patches.