Slovenia-based ACROS Security this week announced the release of patches that address additional attack vectors for the PetitPotam vulnerability.
Disclosed in late July, PetitPotam is a remote code execution vulnerability (CVE-2021-36942) that abuses the Encrypting File System Remote (MS-EFSRPC) protocol.
An attacker exploiting the bug could get a targeted server to connect to an attacker-controlled server and perform NTLM authentication. The attacker could then use other exploits to take complete control of a Windows domain.
Microsoft, which describes PetitPotam as a classic NTLM Relay Attack, has released both mitigations and a fix for the vulnerability.
According to ACROS Security, which previously released a set of micropatches to address the issue, none of the previously released patches covered all of the vulnerable PetitPotam code entirely.
On Thursday, however, the company announced the availability of a new set of micropatches that are meant to fully address the vulnerability. The fixes, ACROS Security says, are meant to complement the security update Microsoft released on its August 2021 patch day.
“New PetitPotam micropatches have just been released, addressing additional known attack vectors that both our first micropatch and Windows Update did not address. With August 2021 Windows Updates installed and 0patch in place, PetitPotam should not work anymore,” the company says.
ACROS Security’s micro patches are available for free for personal use and educational institutions, through their 0patch service. A paid version of the service is also available, for enterprises and for those looking to use the patches work-related.
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