{"id":"CVE-2026-80843","summary":"xfrm: fix xfrm_state_construct() auth-trunc leak","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nxfrm: fix xfrm_state_construct() auth-trunc leak\n\nattach_auth_trunc() can allocate x-\u003eaalg while leaving\nx-\u003eprops.aalgo at zero when the selected auth algorithm has no\nsadb_alg_id. One real case is cmac(aes).\n\nxfrm_state_construct() then treats !x-\u003eprops.aalgo as \"no auth\nalgorithm attached yet\" and calls attach_auth(). That overwrites\nx-\u003eaalg and loses the first allocation. Any later failure or teardown\nonly frees the replacement pointer.\n\nCheck whether x-\u003eaalg is already attached instead of inferring that\nstate from x-\u003eprops.aalgo.","modified":"2026-09-06T03:46:53.464579710Z","published":"2026-09-04T15:54:53.328Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80843.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3"},{"type":"WEB","url":"https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39"},{"type":"WEB","url":"https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca"},{"type":"WEB","url":"https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c"},{"type":"WEB","url":"https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213"},{"type":"WEB","url":"https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795"},{"type":"WEB","url":"https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/80xxx/CVE-2026-80843.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-80843"},{"type":"PACKAGE","url":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","events":[{"introduced":"4447bb33f09444920a8f1d89e1540137429351b6"},{"fixed":"958ae9f261319e1cdc44879886bcda2263258cca"},{"fixed":"fb7f3e74789a3c89647f4eb768f6dfaf4a751e72"},{"fixed":"ba0c110c205855b3f1e3130d8c0fdb484d704c8c"},{"fixed":"c8837bbe792257af547fd1c0252553ce13148795"},{"fixed":"71d42da01740ec6557837bebec0bc48cfc3b4c39"},{"fixed":"cf67361e78dca488d6e4df8396a53e6745a3a80e"},{"fixed":"37426395cb90ef217beec8407a14bd82153793d3"},{"fixed":"be19d20e53a239572bb2a28efcc1cd2b069b1ef9"},{"fixed":"c12cbf56320fb633484ee0ca1fb7d68d6b64b213"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80843.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"2.6.33"},{"fixed":"5.10.269"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.220"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.187"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.156"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.108"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.49"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.13"}]},{"type":"ECOSYSTEM","events":[{"introduced":"7.2.0"},{"fixed":"7.2.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-80843.json"}}],"schema_version":"1.9.0"}