{"id":"CVE-2026-45259","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-45259","generatedAt":"2026-10-28T01:43:47.275Z","title":"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.","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.\n\nA 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.","published":"2026-06-27T09:16:23.000Z","lastModified":"2026-07-01T14:04:52.000Z","status":"Analyzed","sourceIdentifier":"secteam@freebsd.org","cvss":{"version":"3.1","score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H"},"cwe":["CWE-266"],"affected":["freebsd/freebsd"],"epss":{"score":0.00132,"percentile":0.02752,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.13%). Track it; it rarely justifies an emergency change on its own."},"changes":[],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:28.capsicum.asc","tags":["Vendor Advisory"],"source":"secteam@freebsd.org"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-45259","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}