{"id":"CVE-2026-80843","state":"PUBLISHED","title":"xfrm: fix xfrm_state_construct() auth-trunc leak","description":"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->aalg while leaving\nx->props.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->props.aalgo as \"no auth\nalgorithm attached yet\" and calls attach_auth(). That overwrites\nx->aalg and loses the first allocation. Any later failure or teardown\nonly frees the replacement pointer.\n\nCheck whether x->aalg is already attached instead of inferring that\nstate from x->props.aalgo.","publishedAt":"2026-09-04T15:54:53.328Z","updatedAt":"2026-10-19T08:44:36.352Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"958ae9f261319e1cdc44879886bcda2263258cca","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"fb7f3e74789a3c89647f4eb768f6dfaf4a751e72","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"ba0c110c205855b3f1e3130d8c0fdb484d704c8c","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"c8837bbe792257af547fd1c0252553ce13148795","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"71d42da01740ec6557837bebec0bc48cfc3b4c39","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"cf67361e78dca488d6e4df8396a53e6745a3a80e","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"37426395cb90ef217beec8407a14bd82153793d3","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"be19d20e53a239572bb2a28efcc1cd2b069b1ef9","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"c12cbf56320fb633484ee0ca1fb7d68d6b64b213","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_user.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.33","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.33","versionType":"semver"},{"version":"5.10.269","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.220","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.187","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.156","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.108","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.49","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.13","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2.3","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_user.c"]}],"references":["https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca","https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72","https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c","https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795","https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39","https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e","https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3","https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9","https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:07.220Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/80xxx/CVE-2026-80843.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-80843","state":"PUBLISHED","datePublished":"2026-09-04T15:54:53.328Z","dateUpdated":"2026-10-19T08:44:36.352Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-08-26T14:34:25.796Z"},"containers":{"cna":{"title":"xfrm: fix xfrm_state_construct() auth-trunc leak","descriptions":[{"lang":"en","value":"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->aalg while leaving\nx->props.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->props.aalgo as \"no auth\nalgorithm attached yet\" and calls attach_auth(). That overwrites\nx->aalg and loses the first allocation. Any later failure or teardown\nonly frees the replacement pointer.\n\nCheck whether x->aalg is already attached instead of inferring that\nstate from x->props.aalgo."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"958ae9f261319e1cdc44879886bcda2263258cca","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"fb7f3e74789a3c89647f4eb768f6dfaf4a751e72","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"ba0c110c205855b3f1e3130d8c0fdb484d704c8c","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"c8837bbe792257af547fd1c0252553ce13148795","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"71d42da01740ec6557837bebec0bc48cfc3b4c39","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"cf67361e78dca488d6e4df8396a53e6745a3a80e","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"37426395cb90ef217beec8407a14bd82153793d3","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"be19d20e53a239572bb2a28efcc1cd2b069b1ef9","versionType":"git"},{"version":"4447bb33f09444920a8f1d89e1540137429351b6","status":"affected","lessThan":"c12cbf56320fb633484ee0ca1fb7d68d6b64b213","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_user.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"2.6.33","status":"affected"},{"version":"0","status":"unaffected","lessThan":"2.6.33","versionType":"semver"},{"version":"5.10.269","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.220","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.187","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.156","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.108","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.49","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.1.13","status":"unaffected","lessThanOrEqual":"7.1.*","versionType":"semver"},{"version":"7.2.3","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/xfrm/xfrm_user.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/958ae9f261319e1cdc44879886bcda2263258cca"},{"url":"https://git.kernel.org/stable/c/fb7f3e74789a3c89647f4eb768f6dfaf4a751e72"},{"url":"https://git.kernel.org/stable/c/ba0c110c205855b3f1e3130d8c0fdb484d704c8c"},{"url":"https://git.kernel.org/stable/c/c8837bbe792257af547fd1c0252553ce13148795"},{"url":"https://git.kernel.org/stable/c/71d42da01740ec6557837bebec0bc48cfc3b4c39"},{"url":"https://git.kernel.org/stable/c/cf67361e78dca488d6e4df8396a53e6745a3a80e"},{"url":"https://git.kernel.org/stable/c/37426395cb90ef217beec8407a14bd82153793d3"},{"url":"https://git.kernel.org/stable/c/be19d20e53a239572bb2a28efcc1cd2b069b1ef9"},{"url":"https://git.kernel.org/stable/c/c12cbf56320fb633484ee0ca1fb7d68d6b64b213"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:44:36.352Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"5.10.269"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"5.15.220"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"6.1.187"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"6.6.156"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"6.12.108"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"6.18.49"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"7.1.13"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"7.2.3"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"2.6.33","versionEndExcluding":"7.3"}]}]}],"x_generator":{"en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