CVE-2026-45259

Summary

sigqueue(2) was marked as permitted in capability mode with the introduction of Capsicum in 2011, but the implementation of kern_sigqueue did not include a capability mode check restricting signal delivery to the calling process's own PID.

A process in capability mode can use sigqueue(2) to send signals to any process it could signal following standard Unix permissions, bypassing the Capsicum sandbox restriction. A compromised sandboxed process could interfere with other processes, for example by sending SIGKILL or SIGSTOP. This could be any process running as the same user, or any process, for a superuser sandboxed process.

Affected Software

VendorProductVersion RangeStatus
FreeBSDFreeBSD15.0-RELEASE < p10affected
FreeBSDFreeBSD14.4-RELEASE < p6affected
FreeBSDFreeBSD14.3-RELEASE < p15affected

Weaknesses

  • CWE-266: CWE-266: Incorrect Privilege Assignment

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References