{"id":"AZL-80744","summary":"CVE-2026-23279 affecting package kernel for versions less than 6.6.130.1-1","details":"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-\u003emesh_chansw_params_ie is dereferenced\nat lines 1638 and 1642 without a prior NULL check:\n\n    ifmsh-\u003echsw_ttl = elems-\u003emesh_chansw_params_ie-\u003emesh_ttl;\n    ...\n    pre_value = le16_to_cpu(elems-\u003emesh_chansw_params_ie-\u003emesh_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-\u003emesh_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).","modified":"2026-08-28T17:47:54.879250203Z","published":"2026-03-25T11:16:22Z","upstream":["CVE-2026-23279"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-23279"}],"affected":[{"package":{"name":"kernel","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/kernel"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"6.6.130.1-1"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-80744.json"}}],"schema_version":"1.9.0"}