Linux Linux Kernel
CVE-2026-64440
In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix OOB write in HT_caps_handler() HT_caps_handler() iterates pIE->length bytes and writes into HT_caps.u.HT_cap[], which is a fixed 26-byte array (sizeof struct HT_caps_element). Because pIE->length is a raw u8 from an over-the-air 802.11 AssocResponse frame and is never validated, a malicious AP can set it up to 255, causing up to 229 bytes of out-of-bounds writes into adjacent fields of struct mlme_ext_info. Truncate the iteration count to the size of HT_caps.u.HT_cap using umin() so that data from a longer-than-expected IE is silently ignored rather than written out of bounds, preserving interoperability with APs that pad the element. An early return on oversized IEs was considered but rejected: it would bypass the pmlmeinfo->HT_caps_enable = 1 assignment that precedes the loop, silently disabling HT mode for APs that append extra bytes to the HT Capabilities IE.
What this means for your business
- It affects Linux Kernel. It matters if your company, or a supplier that handles your data, runs it.
- An attacker can use it from inside the same network, without a login, and without anyone at your company clicking anything.
- FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 33% of all known flaws.
What to do
- 1Check whether your company or your suppliers run Linux Kernel, and which version. The affected versions are listed further down this page.
- 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.
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Scoring
- CVSS
- 8.1 (v3.1)
- Vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H- Weakness
- CWE-787
- Assigned by
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Dates
- Published
- 2026-07-25
- Last modified
- 2026-09-03
- Sources
- NVD
Affected products
- Linux Linux Kernel4.12 - 5.15.212, 5.16 - 6.1.178, 6.2 - 6.6.145, 6.7 - 6.12.96, 6.13 - 6.18.39, 6.19 - 7.1.4, 7.2
As listed in the NVD configuration data. Not a statement about your estate.
References
- https://git.kernel.org/stable/c/225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d
- https://git.kernel.org/stable/c/37f642d47c3648a707df3ceb092eee1adffbfd28
- https://git.kernel.org/stable/c/6f91621fc45025ad3c0be796b70e6e4cee22fc69
- https://git.kernel.org/stable/c/8c872b47c7fc32e95e0da1db7512388794adcd69
- https://git.kernel.org/stable/c/918537a0fbed85aab61fa28ad75e6279070610c9
- https://git.kernel.org/stable/c/bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a
- https://git.kernel.org/stable/c/f8001e1a516ba3b495728c65b61f799cbfad6bd0