CVE-2026-64223: Linux kernel · wifi: mac80211: consume only present negotiated TTLM maps
Affects Linux kernelSource CVE Database V5
Not known to be exploited · CVSS 8.1 High · fixed in f7d395dc5008168ac5b9c1ac2791e59a6078cca1 : patch Linux kernel soon.
Data as of 26 Oct 2026, 13:47 UTC
- EPSS
- 0.3% chance of exploitation in 30 days – higher than 32% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- CISA SSVC
- Exploitation
- No evidence of active exploitation and no public proof of concept
- Automatable
- Attackers cannot reliably automate steps 1–4 of the kill chain
- Technical impact
- Limited control over the software or limited information exposure
CISA SSVC assessment, 2026-10-16.
- Patch
- Available – fixed in f7d395dc5008168ac5b9c1ac2791e59a6078cca1, a6e6ccd5bd07155c2add6c74ce1a5e68ad3b95ea, 2dd9304727c7041df0a599595910bdbe02ad03c5 +1
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 24 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.
What to do
Upgrade Linux kernel to f7d395dc5008168ac5b9c1ac2791e59a6078cca1, a6e6ccd5bd07155c2add6c74ce1a5e68ad3b95ea, 2dd9304727c7041df0a599595910bdbe02ad03c5 or 2becaaeebe230ade1fcd5d0f1cde4d6ee93ec78f.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in
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| LinuxLinux | Affected
| Fixed in– |
Description
In the Linux kernel, the following vulnerability has been resolved: wifi: mac80211: consume only present negotiated TTLM maps ieee80211_tid_to_link_map_size_ok() validates negotiated TTLM elements against the number of link-map entries indicated by link_map_presence. ieee80211_parse_neg_ttlm() must consume the same layout. The parser advanced its cursor for every TID, including TIDs whose presence bit is clear and therefore have no map bytes in the element. A sparse map can then make a later present TID read past the validated element. The bad bytes land in neg_ttlm->{up,down}link[tid] but are gated by valid_links before being applied to driver state, so a peer cannot turn the read into a policy change. Under KUnit + KASAN with an exact-sized element allocation the OOB read is reported as a slab-out-of-bounds; whether the same trigger fires under the production RX path depends on surrounding allocator state. Advance the cursor only when the current TID has a map present.
References
- git.kernel.org/stable/c/f7d395dc5008168ac5b9c1ac2791e59a6078cca1 (opens in a new tab)
- git.kernel.org/stable/c/2dd9304727c7041df0a599595910bdbe02ad03c5 (opens in a new tab)
- git.kernel.org/stable/c/2becaaeebe230ade1fcd5d0f1cde4d6ee93ec78f (opens in a new tab)
- git.kernel.org/stable/c/a6e6ccd5bd07155c2add6c74ce1a5e68ad3b95ea (opens in a new tab)