{"id":"CVE-2026-16141","summary":"OpenBMC IPMI Authentication Bypass via Default userKey and Stale Challenge Value","details":"OpenBMC's IPMI implementation, phosphor-net-ipmid, contains a logic flaw in which an unauthenticated client can force the RAKP Message 1 handler to return before it overwrites the authentication object's constructor defaults. The IPMI service then accepts a RAKP Message 3 whose HMAC is computed with the constant 20-byte 'userKey' initialized from the string '0penBmc' and an often-predictable 'bmcRandomNum'. Several downstream vendors implement phosphor-net-ipmid as their IPMI stack, such as NVIDIA and H3C.","modified":"2026-10-08T02:49:21.119714852Z","published":"2026-09-15T13:57:28.846Z","database_specific":{"cna_assigner":"runZero","cwe_ids":["CWE-457","CWE-798"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16141.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/16xxx/CVE-2026-16141.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-16141"},{"type":"ADVISORY","url":"https://www.runzero.com/advisories/openbmc-ipmi-auth-bypass-rakp-cve-2026-16141/"},{"type":"PACKAGE","url":"https://github.com/openbmc/phosphor-net-ipmid"},{"type":"ARTICLE","url":"https://www.runzero.com/blog/lights-out-exposed/"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/openbmc/phosphor-net-ipmid","events":[{"introduced":"0"},{"last_affected":"ba6efc502e6b1fabb8ed1ca677ae5eedd64b6361"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-16141.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}