New Linux ‘Copy Fail’ Vulnerability Enables Root Access on Major Distributions
A Linux local privilege escalation (LPE) vulnerability that might provide an unauthorized local user access to root has been revealed by cybersecurity experts.
Xint.io and Theori have nicknamed the high-severity vulnerability CVE-2026-31431 (CVSS score: 7.8) as Copy Fail. According to the vulnerability research team at Xint.io and Theori, an unprivileged local user can get root by writing four controlled bytes into the page cache of any readable file on a Linux machine.
Fundamentally, the vulnerability is caused by a logic error in the algif_aead module of the cryptography subsystem of the Linux kernel. August 2017 saw the introduction of the problem in a source code commit.
If the vulnerability is successfully exploited, a straightforward 732-byte Python script might modify a se...