CVE-2026-93222: signal: avoid shared siginfo namespace rewrites
In the Linux kernel, the following vulnerability has been resolved:
signal: avoid shared siginfo namespace rewrites
sendsignallocked() rewrites sender ids for the target namespace. Group sends reuse the same siginfo, so one recipient can affect the next.
Copy the siginfo before changing it.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
Copy the siginfo before changing it to prevent one recipient from affecting the next when sends reuse the same siginfo.
Event History
Frequently Asked Questions
What conditions are required for this issue to occur?
The issue occurs during group signal delivery when the same siginfo structure is reused for multiple recipients. Rewriting sender IDs for one recipient's target namespace can then affect the siginfo seen by subsequent recipients.
What is the impact on affected systems?
Signal sender identifiers can be rewritten using the wrong namespace context for later recipients of a group signal. This can cause recipients to observe incorrect sender identity information.
Is there a mitigation if the fix cannot be applied immediately?
No mitigation is provided in the available information. The referenced kernel changes address the issue by copying siginfo before modifying sender IDs for a target namespace.