Copy Fail: privilege escalation in the Linux kernel
A flaw in the kernel cryptographic interface lets a user with a local account gain administrator privileges; Red Hat rates it as Important.
What happened
Vulnerability CVE-2026-31431 sits in the Linux kernel cryptographic interface and allows a user with a local account to gain administrator privileges, that is, root. Red Hat rates it as Important and publishes fixes for all of its products.
Why it matters
It does not allow entry from outside, but it turns an ordinary account into full control of the server. On a shared machine, or on one where someone has obtained a limited account, the difference between user and root is the whole difference: from there all data can be read, the service can be stopped and a door can be left to come back. A flaw that needs a local account looks minor, yet most incidents start precisely with a valid, unprivileged user credential.
What we recommend
Review Linux servers and apply the fix for each distribution. Until it is patched, the mitigation is to limit local access: the fewer accounts that can log in to the machine, the less surface there is to reach root. It is also worth reviewing which service accounts are still active and whether any of them should not be able to log in. If the server cannot be touched this week, limiting access stops being a recommendation and becomes the only barrier available.
Related service: infraestructura-cloud
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