What’s Vulnerable › Vulnerabilities
CVE-2026-45259: sigqueue(2) missing capability mode restriction
- Severity: medium (CVSS 6.5 v3.1)
- Exploited in the wild: not listed in CISA KEV
- EPSS: 0.1% probability of exploitation in the next 30 days
- Public exploit or detection template: none known
- Published: 2026-06-27 · updated 2026-07-01
- Weakness: CWE-266
Description
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 products
- FreeBSD: 14.3, 14.3-p1, 14.3-p10, 14.3-p11, 14.3-p12, 14.3-p13 (+25)
References
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