{"cve":"CVE-2026-23279","nvd":{"published":"2026-03-25T11:16:22.333","modified":"2026-10-15T02:18:46.597","status":"Modified","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).","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","score":5.5},"cwes":["CWE-476"],"references":["https://git.kernel.org/stable/c/017c1792525064a723971f0216e6ef86a8c7af11","https://git.kernel.org/stable/c/22a9adea7e26d236406edc0ea00b54351dd56b9c","https://git.kernel.org/stable/c/2b5f282b1b7241ef624c3399a1cdff0bb1a3eeab","https://git.kernel.org/stable/c/753ad20dcbe36b67088c7770d8fc357d7cc43e08","https://git.kernel.org/stable/c/be8b82c567fda86f2cbb43b7208825125bb31421"],"products":["linux:linux_kernel"],"source":"nvd","synced_at":"2026-10-19T22:26:19.218427112+00:00"},"epss":{"cve":"CVE-2026-23279","score":0.00145,"percentile":0.03699,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}