{"id":"CVE-2026-64440","summary":"staging: rtl8723bs: fix OOB write in HT_caps_handler()","details":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: rtl8723bs: fix OOB write in HT_caps_handler()\n\nHT_caps_handler() iterates pIE-\u003elength bytes and writes into\nHT_caps.u.HT_cap[], which is a fixed 26-byte array (sizeof struct\nHT_caps_element). Because pIE-\u003elength is a raw u8 from an over-the-air\n802.11 AssocResponse frame and is never validated, a malicious AP can\nset it up to 255, causing up to 229 bytes of out-of-bounds writes into\nadjacent fields of struct mlme_ext_info.\n\nTruncate the iteration count to the size of HT_caps.u.HT_cap using\numin() so that data from a longer-than-expected IE is silently ignored\nrather than written out of bounds, preserving interoperability with APs\nthat pad the element. An early return on oversized IEs was considered\nbut rejected: it would bypass the pmlmeinfo-\u003eHT_caps_enable = 1\nassignment that precedes the loop, silently disabling HT mode for APs\nthat append extra bytes to the HT Capabilities IE.","modified":"2026-07-28T04:03:07.222122390Z","published":"2026-07-25T08:51:13.138Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64440.json","cna_assigner":"Linux"},"references":[{"type":"WEB","url":"https://git.kernel.org/stable/c/225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d"},{"type":"WEB","url":"https://git.kernel.org/stable/c/37f642d47c3648a707df3ceb092eee1adffbfd28"},{"type":"WEB","url":"https://git.kernel.org/stable/c/6f91621fc45025ad3c0be796b70e6e4cee22fc69"},{"type":"WEB","url":"https://git.kernel.org/stable/c/8c872b47c7fc32e95e0da1db7512388794adcd69"},{"type":"WEB","url":"https://git.kernel.org/stable/c/918537a0fbed85aab61fa28ad75e6279070610c9"},{"type":"WEB","url":"https://git.kernel.org/stable/c/bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a"},{"type":"WEB","url":"https://git.kernel.org/stable/c/f8001e1a516ba3b495728c65b61f799cbfad6bd0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/64xxx/CVE-2026-64440.json"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64440"},{"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":"554c0a3abf216c991c5ebddcdb2c08689ecd290b"},{"fixed":"37f642d47c3648a707df3ceb092eee1adffbfd28"},{"fixed":"8c872b47c7fc32e95e0da1db7512388794adcd69"},{"fixed":"bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a"},{"fixed":"918537a0fbed85aab61fa28ad75e6279070610c9"},{"fixed":"6f91621fc45025ad3c0be796b70e6e4cee22fc69"},{"fixed":"225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d"},{"fixed":"f8001e1a516ba3b495728c65b61f799cbfad6bd0"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64440.json"}},{"package":{"name":"Kernel","ecosystem":"Linux"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"4.12.0"},{"fixed":"5.15.212"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.178"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.145"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.96"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.39"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.19.0"},{"fixed":"7.1.4"}]}],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-64440.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H"}]}