{"id":"CVE-2026-56099","summary":"OpenBSD mpls_do_error Kernel Stack Memory Disclosure via MPLS Input","details":"OpenBSD before commit 6a23123 (2026-06-18) contains an out-of-bounds read vulnerability in the mpls_do_error function within sys/netmpls/mpls_input.c that allows remote attackers to disclose kernel stack memory by sending crafted MPLS frames with 16 labels and no Bottom-of-Stack bit set.","modified":"2026-10-21T10:24:40.718169368Z","published":"2026-06-18T19:29:08.271Z","database_specific":{"cna_assigner":"VulnCheck","cwe_ids":["CWE-125"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56099.json"},"references":[{"type":"WEB","url":"http://seclists.org/fulldisclosure/2026/Jun/17"},{"type":"WEB","url":"http://www.openwall.com/lists/oss-security/2026/06/19/3"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/56xxx/CVE-2026-56099.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-56099"},{"type":"ADVISORY","url":"https://www.vulncheck.com/advisories/openbsd-mpls-do-error-kernel-stack-memory-disclosure-via-mpls-input"},{"type":"FIX","url":"https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"},{"type":"PACKAGE","url":"https://github.com/openbsd/src"},{"type":"EVIDENCE","url":"https://pop.argus-systems.ai/advisory/adv-040.html"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openbsd/src","events":[{"introduced":"0"},{"fixed":"6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"}],"database_specific":{"extracted_events":[{"source":"AFFECTED_FIELD","strategy":"StandardRange","range":[{"introduced":"0"},{"fixed":"6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"}]},{"source":"REFERENCES_COMMIT","range":[{"fixed":"6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"}]}]}}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-56099.json","vanir_signatures":[{"target":{"file":"sys/netmpls/mpls_input.c"},"deprecated":false,"digest":{"threshold":0.9,"line_hashes":["214501725817765619687789676424629373910","171745048645506414789133289662303457947","183165387675308835546541401840556237993","270311563117041349745719620477978035278","335522886547838601549901776027989373454"]},"id":"CVE-2026-56099-743cd715","signature_type":"Line","signature_version":"v1","source":"https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd"},{"signature_version":"v1","source":"https://github.com/openbsd/src/commit/6a23123ec05f1eb29cfcaae0f3a468b2e1983cfd","target":{"file":"sys/netmpls/mpls_input.c","function":"mpls_do_error"},"deprecated":false,"digest":{"function_hash":"290605894353759007932632249171159928095","length":2430},"id":"CVE-2026-56099-b2790f1d","signature_type":"Function"}],"vanir_signatures_modified":"2026-10-21T10:24:40Z"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"}]}