{"id":"CVE-2026-64255","summary":"wifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: iwlwifi: mld: validate sta_mask before ffs() in BA session handlers\n\nThree BA session handlers use ffs(ba_data-\u003esta_mask) - 1 to derive a\nstation ID without checking that sta_mask is non-zero. When sta_mask is\nzero, ffs() returns 0 and the subtraction wraps to 0xFFFFFFFF, causing\nan out-of-bounds access on fw_id_to_link_sta[].\n\nAdd WARN_ON_ONCE(!ba_data-\u003esta_mask) guards before each ffs() call,\nconsistent with the existing check in iwl_mld_ampdu_rx_start().","modified":"2026-08-18T03:31:14.224794788Z","published":"2026-07-24T15:31:22.870Z","related":["openSUSE-SU-2026:11476-1"],"database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64255.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/1de92789ce31e46fa7e7d8e89c90b19cdb1c103b"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f056fc2b927448d37eca6b6cacc3d1b0f67b20d2"},{"type":"WEB","url":"https://git.kernel.org/stable/c/fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64255.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64255"},{"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":"9aa3856d9b6f3f8bf085b5bbb5f3703578bf452b"},{"fixed":"1de92789ce31e46fa7e7d8e89c90b19cdb1c103b"},{"fixed":"fe7f339f63c9dc4ca546ed7ac38ba4bb3a99dcfc"},{"fixed":"f056fc2b927448d37eca6b6cacc3d1b0f67b20d2"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64255.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.4.0"},{"fixed":"6.18.38"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.3"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64255.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}