CVE Catalog

CVE-2026-80928

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.13%

2th percentile - higher than 2% of all known CVEs

Summary

In the Linux kernel, smack_file_send_sigiotask() was accessing both tsk->cred and __task_cred(tsk). Accessing ->cred on a non-current task is forbidden because a task can change its own ->cred pointer without synchronization, leading to a use-after-free of struct cred.

Risk Assessment

The use-after-free race of struct cred can lead to kernel memory corruption and system crash (KASAN reported UAF). It can be triggered by signal I/O operations to a task.

Recommendation

Update the Linux kernel to a version with the fix that always accesses the objective credentials (__task_cred(tsk)) in smack_file_send_sigiotask().

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: smack: fix cred UAF in smack_file_send_sigiotask() When inspecting the credentials of another task, objective credentials (->real_cred, accessed with __task_cred()) must always be used. Accessing ->cred on a non-current task is forbidden unless that task is being created or destroyed; a task is allowed to change its own ->cred pointer with no synchronization, and changing ->cred should only affect the current syscall. smack_file_send_sigiotask() was accessing both sets of credentials: First tsk->cred, then __task_cred(tsk). Fix it, always access the objective credentials here. I have tested that this bug can lead to a KASAN-reported UAF of struct cred in smack_file_send_sigiotask(), and that this fix prevents the race.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS