{"id":"CVE-2026-23279","state":"PUBLISHED","title":"wifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame()\n\nIn mesh_rx_csa_frame(), elems->mesh_chansw_params_ie is dereferenced\nat lines 1638 and 1642 without a prior NULL check:\n\n    ifmsh->chsw_ttl = elems->mesh_chansw_params_ie->mesh_ttl;\n    ...\n    pre_value = le16_to_cpu(elems->mesh_chansw_params_ie->mesh_pre_value);\n\nThe mesh_matches_local() check above only validates the Mesh ID,\nMesh Configuration, and Supported Rates IEs.  It does not verify the\npresence of the Mesh Channel Switch Parameters IE (element ID 118).\nWhen a received CSA action frame omits that IE, ieee802_11_parse_elems()\nleaves elems->mesh_chansw_params_ie as NULL, and the unconditional\ndereference causes a kernel NULL pointer dereference.\n\nA remote mesh peer with an established peer link (PLINK_ESTAB) can\ntrigger this by sending a crafted SPECTRUM_MGMT/CHL_SWITCH action frame\nthat includes a matching Mesh ID and Mesh Configuration IE but omits the\nMesh Channel Switch Parameters IE.  No authentication beyond the default\nopen mesh peering is required.\n\nCrash confirmed on kernel 6.17.0-5-generic via mac80211_hwsim:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n  Oops: Oops: 0000 [#1] SMP NOPTI\n  RIP: 0010:ieee80211_mesh_rx_queued_mgmt+0x143/0x2a0 [mac80211]\n  CR2: 0000000000000000\n\nFix by adding a NULL check for mesh_chansw_params_ie after\nmesh_matches_local() returns, consistent with how other optional IEs\nare guarded throughout the mesh code.\n\nThe bug has been present since v3.13 (released 2014-01-19).","publishedAt":"2026-03-25T10:26:39.994Z","updatedAt":"2026-10-15T01:13:36.414Z","severity":null,"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"753ad20dcbe36b67088c7770d8fc357d7cc43e08","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"f061336f072ab03fd29270ae61fede46bf8fd69d","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"22a9adea7e26d236406edc0ea00b54351dd56b9c","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"f5d8af683410a8c82e48b51291915bd612523d9a","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"cc6d5a3c0a854aeae00915fc5386570c86029c60","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"be8b82c567fda86f2cbb43b7208825125bb31421","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"017c1792525064a723971f0216e6ef86a8c7af11","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/mesh.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.13","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.77","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.17","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.7","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/mesh.c"]}],"references":["https://git.kernel.org/stable/c/753ad20dcbe36b67088c7770d8fc357d7cc43e08","https://git.kernel.org/stable/c/f061336f072ab03fd29270ae61fede46bf8fd69d","https://git.kernel.org/stable/c/2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab","https://git.kernel.org/stable/c/22a9adea7e26d236406edc0ea00b54351dd56b9c","https://git.kernel.org/stable/c/f5d8af683410a8c82e48b51291915bd612523d9a","https://git.kernel.org/stable/c/cc6d5a3c0a854aeae00915fc5386570c86029c60","https://git.kernel.org/stable/c/be8b82c567fda86f2cbb43b7208825125bb31421","https://git.kernel.org/stable/c/017c1792525064a723971f0216e6ef86a8c7af11","https://cert-portal.siemens.com/productcert/html/ssa-784472.html"],"weaknesses":[],"ingestedAt":"2026-10-29T20:11:21.040Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/23xxx/CVE-2026-23279.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-23279","state":"PUBLISHED","datePublished":"2026-03-25T10:26:39.994Z","dateUpdated":"2026-10-15T01:13:36.414Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-01-13T15:37:45.992Z"},"containers":{"cna":{"title":"wifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: fix NULL pointer dereference in mesh_rx_csa_frame()\n\nIn mesh_rx_csa_frame(), elems->mesh_chansw_params_ie is dereferenced\nat lines 1638 and 1642 without a prior NULL check:\n\n    ifmsh->chsw_ttl = elems->mesh_chansw_params_ie->mesh_ttl;\n    ...\n    pre_value = le16_to_cpu(elems->mesh_chansw_params_ie->mesh_pre_value);\n\nThe mesh_matches_local() check above only validates the Mesh ID,\nMesh Configuration, and Supported Rates IEs.  It does not verify the\npresence of the Mesh Channel Switch Parameters IE (element ID 118).\nWhen a received CSA action frame omits that IE, ieee802_11_parse_elems()\nleaves elems->mesh_chansw_params_ie as NULL, and the unconditional\ndereference causes a kernel NULL pointer dereference.\n\nA remote mesh peer with an established peer link (PLINK_ESTAB) can\ntrigger this by sending a crafted SPECTRUM_MGMT/CHL_SWITCH action frame\nthat includes a matching Mesh ID and Mesh Configuration IE but omits the\nMesh Channel Switch Parameters IE.  No authentication beyond the default\nopen mesh peering is required.\n\nCrash confirmed on kernel 6.17.0-5-generic via mac80211_hwsim:\n\n  BUG: kernel NULL pointer dereference, address: 0000000000000000\n  Oops: Oops: 0000 [#1] SMP NOPTI\n  RIP: 0010:ieee80211_mesh_rx_queued_mgmt+0x143/0x2a0 [mac80211]\n  CR2: 0000000000000000\n\nFix by adding a NULL check for mesh_chansw_params_ie after\nmesh_matches_local() returns, consistent with how other optional IEs\nare guarded throughout the mesh code.\n\nThe bug has been present since v3.13 (released 2014-01-19)."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"753ad20dcbe36b67088c7770d8fc357d7cc43e08","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"f061336f072ab03fd29270ae61fede46bf8fd69d","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"22a9adea7e26d236406edc0ea00b54351dd56b9c","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"f5d8af683410a8c82e48b51291915bd612523d9a","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"cc6d5a3c0a854aeae00915fc5386570c86029c60","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"be8b82c567fda86f2cbb43b7208825125bb31421","versionType":"git"},{"version":"8f2535b92d685c68db4bc699dd78462a646f6ef9","status":"affected","lessThan":"017c1792525064a723971f0216e6ef86a8c7af11","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/mesh.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"3.13","status":"affected"},{"version":"0","status":"unaffected","lessThan":"3.13","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.167","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.130","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.77","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.17","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.7","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/mac80211/mesh.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/753ad20dcbe36b67088c7770d8fc357d7cc43e08"},{"url":"https://git.kernel.org/stable/c/f061336f072ab03fd29270ae61fede46bf8fd69d"},{"url":"https://git.kernel.org/stable/c/2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab"},{"url":"https://git.kernel.org/stable/c/22a9adea7e26d236406edc0ea00b54351dd56b9c"},{"url":"https://git.kernel.org/stable/c/f5d8af683410a8c82e48b51291915bd612523d9a"},{"url":"https://git.kernel.org/stable/c/cc6d5a3c0a854aeae00915fc5386570c86029c60"},{"url":"https://git.kernel.org/stable/c/be8b82c567fda86f2cbb43b7208825125bb31421"},{"url":"https://git.kernel.org/stable/c/017c1792525064a723971f0216e6ef86a8c7af11"}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-05-11T22:03:47.541Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.1.167"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.6.130"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.12.77"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.18.17"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"6.19.7"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"3.13","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"affected":[{"vendor":"Siemens","product":"SIMATIC S7-1500 TM MFP - GNU/Linux subsystem","defaultStatus":"unknown","versions":[{"version":"0","status":"affected","lessThan":"*","versionType":"custom"}]}],"references":[{"url":"https://cert-portal.siemens.com/productcert/html/ssa-784472.html"}],"providerMetadata":{"shortName":"siemens-SADP","orgId":"0b142b55-0307-4c5a-b3c9-f314f3fb7c5e","dateUpdated":"2026-10-15T01:13:36.414Z"},"x_adpType":"supplier"}]}}}