{"id":"CVE-2026-58087","state":"PUBLISHED","title":"Heap out-of-bounds access in semctl(2)","description":"The GETALL and SETALL commands in semctl(2) recorded the number of semaphores in the target set, dropped the lock protecting the set, allocated a buffer sized for that count, and reacquired the lock.  A sequence-number check was used to verify that the set had not been replaced in the interim, but the sequence number wraps after 0x8000 create/destroy cycles.  By rapidly destroying and recreating semaphore sets at the same index, another process can cause the sequence number to wrap, allowing a set with a different number of semaphores to pass validation.  The subsequent copy then reads or writes past the end of the allocated buffer.\n\nAn unprivileged local user can trigger out-of-bounds reads and writes on kernel heap memory, potentially leading to privilege escalation.","publishedAt":"2026-08-19T07:47:50.665Z","updatedAt":"2026-08-20T03:55:43.754Z","severity":{"score":7.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","source":"CISA-ADP"},"assigner":"freebsd","products":["FreeBSD FreeBSD"],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.1-RELEASE","status":"affected","lessThan":"p2","versionType":"release"},{"version":"15.0-RELEASE","status":"affected","lessThan":"p12","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p8","versionType":"release"}],"modules":["sysvsem"]}],"references":["https://security.freebsd.org/advisories/FreeBSD-SA-26:54.sysvsem.asc"],"weaknesses":["CWE-191","CWE-125","CWE-787"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/58xxx/CVE-2026-58087.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-58087","state":"PUBLISHED","datePublished":"2026-08-19T07:47:50.665Z","dateUpdated":"2026-08-20T03:55:43.754Z","assignerShortName":"freebsd","assignerOrgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateReserved":"2026-06-29T01:40:17.498Z"},"containers":{"cna":{"title":"Heap out-of-bounds access in semctl(2)","descriptions":[{"lang":"en","value":"The GETALL and SETALL commands in semctl(2) recorded the number of semaphores in the target set, dropped the lock protecting the set, allocated a buffer sized for that count, and reacquired the lock.  A sequence-number check was used to verify that the set had not been replaced in the interim, but the sequence number wraps after 0x8000 create/destroy cycles.  By rapidly destroying and recreating semaphore sets at the same index, another process can cause the sequence number to wrap, allowing a set with a different number of semaphores to pass validation.  The subsequent copy then reads or writes past the end of the allocated buffer.\n\nAn unprivileged local user can trigger out-of-bounds reads and writes on kernel heap memory, potentially leading to privilege escalation."}],"affected":[{"vendor":"FreeBSD","product":"FreeBSD","defaultStatus":"unknown","versions":[{"version":"15.1-RELEASE","status":"affected","lessThan":"p2","versionType":"release"},{"version":"15.0-RELEASE","status":"affected","lessThan":"p12","versionType":"release"},{"version":"14.4-RELEASE","status":"affected","lessThan":"p8","versionType":"release"}],"modules":["sysvsem"]}],"references":[{"url":"https://security.freebsd.org/advisories/FreeBSD-SA-26:54.sysvsem.asc","tags":["vendor-advisory"]}],"problemTypes":[{"descriptions":[{"cweId":"CWE-191","description":"CWE-191: Integer Underflow (Wrap or Wraparound)","lang":"en","type":"CWE"},{"cweId":"CWE-125","description":"CWE-125: Out-of-bounds Read","lang":"en","type":"CWE"},{"cweId":"CWE-787","description":"CWE-787: Out-of-bounds Write","lang":"en","type":"CWE"}]}],"providerMetadata":{"shortName":"freebsd","orgId":"63664ac6-956c-4cba-a5d0-f46076e16109","dateUpdated":"2026-08-19T07:47:50.665Z"},"datePublic":"2026-07-29T22:40:00.000Z","credits":[{"lang":"en","type":"finder","value":"Maik Muench of Secfault Security"}],"x_generator":{"engine":"cvelib 1.8.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.8,"attackVector":"LOCAL","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H","integrityImpact":"HIGH","userInteraction":"REQUIRED","attackComplexity":"LOW","availabilityImpact":"HIGH","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-08-19T00:00:00+00:00","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3","id":"CVE-2026-58087"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-08-20T03:55:43.754Z"}}]}}}