Details about the 'Copy Fail' vulnerability have been published CVE-2026-31431 (Base Score: 7.8 HIGH), which allows local privilege escalation to root for any local user without special tools or conditions. Most systems released since 2017 are affected.
The vulnerability is related to an error in authencesn — a cryptographic template in the Linux kernel — and is exploited through the AF_ALG interface.
An exploit with Python code of 732 bytes is available.
For all multi-user systems and isolated environments, it is recommended to update the kernel to a version with a rollback of commit 72548b093ee3 upon the release of fixes.
An effective measure to close the vulnerability until an update is to disable the algif_aead module in the kernel. Its deactivation will not notably affect systems where cryptographic tools are not explicitly configured to operate exclusively through AF_ALG.
Source: linux.org.ru
