CVE-2026-68402wifi: cfg80211: bound element ID read when checking non-inheritance

Official description

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: bound element ID read when checking non-inheritance cfg80211_is_element_inherited() reads the first data octet of the candidate element (id = elem->data[0]) to look it up in an extension non-inheritance list. It does so after testing elem->id, but without verifying that the element actually has a data octet. A zero-length extension element (WLAN_EID_EXTENSION with length 0) therefore makes it read one octet past the end of the element. _ieee802_11_parse_elems_full() runs this check for every element of a frame once a non-inheritance context exists -- e.g. while parsing a per-STA profile of a Multi-Link element in a (re)association response, or a non-transmitted BSS profile -- so a crafted frame from an AP can trigger a one-octet slab-out-of-bounds read during element parsing: BUG: KASAN: slab-out-of-bounds in cfg80211_is_element_inherited Read of size 1 ... in net/wireless/scan.c Return early (treat the element as inherited) when an extension element carries no data, mirroring the existing handling of empty ID lists. The bug was found by fuzzing ieee802_11_parse_elems_full() under KASAN.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/521dd5fe6d12b0d3c275f919738dc3a07117f4a5
• https://git.kernel.org/stable/c/24154c172246ae3f0e69bb17c9111095685ceedc
• https://git.kernel.org/stable/c/2d31ebb26a14f103c9cdc5287fb20cb2d4bde901
• https://git.kernel.org/stable/c/20c308d9a57722801961f816395bf825f7bde6bc
• https://git.kernel.org/stable/c/84bd907361c56fbd5523eceb2682cb39da059bd5
• https://git.kernel.org/stable/c/11ac7a5e75f5132f1778e0c60981d30dc29fb869
• https://git.kernel.org/stable/c/ddf2773bcc8e49a43c561f22ec1e7924215d7947
• https://git.kernel.org/stable/c/cb8afea4655ff004fa7feee825d5c79783525383