{"id":"CVE-2026-74336","summary":"wifi: mac80211: bound S1G TIM PVB walk to the TIM element","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mac80211: bound S1G TIM PVB walk to the TIM element\n\nieee80211_s1g_check_tim() parses the S1G Partial Virtual Bitmap (PVB) of a\nreceived TIM element. The TIM is handed in as the element payload:\nieee802_11_parse_elems_full() stores elems-\u003etim = elem-\u003edata and\nelems-\u003etim_len = elem-\u003edatalen (net/mac80211/parse.c), so the valid bytes\nare [tim, tim + tim_len).\n\nWhen walking the encoded blocks the function passes the walker an end\nsentinel of (const u8 *)tim + tim_len + 2, i.e. two bytes past the end of\nthe element. ieee80211_s1g_find_target_block() loops while (ptr + 1 \u003c= end)\nand dereferences ptr (and the per-mode ieee80211_s1g_len_*() helpers read\n*ptr), so it can read up to two bytes beyond the TIM element -- an\nout-of-bounds read of adjacent skb/heap data when the TIM is the last\nelement in the frame. The +2 appears to account for the element id/len\nheader, but tim already points past that header at the element payload, so\nthe addend is wrong.\n\nPass the correct element end, (const u8 *)tim + tim_len.","modified":"2026-08-18T03:30:52.830626048Z","published":"2026-08-15T05:58:27.799Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74336.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/3abc13ec3ac28c343ad7e7b7496e807b924f0edd"},{"type":"WEB","url":"https://git.kernel.org/stable/c/b224d18b1e5d1cddfc67f63f41d80023b2ec8889"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74336.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-74336"},{"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":"e0c47c6229c25b54440fe1f84a0ff533942290b1"},{"fixed":"3abc13ec3ac28c343ad7e7b7496e807b924f0edd"},{"fixed":"b224d18b1e5d1cddfc67f63f41d80023b2ec8889"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74336.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"6.18.0"},{"fixed":"7.1.5"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-74336.json"}}],"schema_version":"1.9.0"}