CVE-2026-80928 Linux CVE debrief

Who should care

Linux kernel maintainers, users, and administrators should assess exposure and verify kernel versions to ensure the fix is applied. Linux distributions and vendors should evaluate and update their kernel packages to protect against potential use-after-free attacks. Security teams and vulnerability management teams should review system configurations and monitor system logs for potential security issues. Operators and platform administrators should verify 3

Why it matters

A use-after-free vulnerability in the Linux kernel's Smack implementation has been addressed. Linux kernel maintainers and users should verify their kernel versions and apply the fix to prevent potential use-after-free attacks.

• Verify kernel version to prevent potential use-after-free attacks
• Review system configurations to ensure Smack is properly configured
• Monitor system logs for potential security issues

Technical summary

The smack_file_send_sigiotask() function in the Linux kernel was accessing both current task credentials (tsk->cred) and objective credentials (__task_cred(tsk)). This could lead to a KASAN-reported use-after-free of struct cred. The issue has been resolved by always accessing the objective credentials. Linux kernel maintainers and users should verify their kernel versions and apply the fix to prevent potential use-after-free attacks. The bug was introduced by accessing both current and objective credentials in the smack_file_send_sigiotask() function, which could result in a use-after-free vulnerability.

Defensive priority

Linux kernel maintainers and users should verify their kernel versions and apply the fix to prevent potential use-after-free attacks.

Recommended defensive actions

• Verify kernel version and apply the fix
• Review system configurations and ensure Smack is properly configured
• Monitor system logs for potential use-after-free attacks
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.
• Track exceptions, retest remediated assets, and close the item only after evidence is documented.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.

Evidence notes

The CVE record and source references indicate a use-after-free vulnerability in the Linux kernel's Smack implementation. The bug was introduced by accessing both current and objective credentials in the smack_file_send_sigiotask() function.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.