Review reviewHigh

CVE-2026-64440

Linux

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...

CVSS
8.1
EPSS
-
- percentile
CISA KEV
Not listed
Published
2026.07.25
PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV
Exploit probability-
Technical severityCVSS 8.1

Vulnerability overview

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...

Affected product and versions

Product
Linux
Affected versions
>= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < 37f642d47c3648a707df3ceb092eee1adffbfd28, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < 8c872b47c7fc32e95e0da1db7512388794adcd69, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < 918537a0fbed85aab61fa28ad75e6279070610c9, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < 6f91621fc45025ad3c0be796b70e6e4cee22fc69, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < 225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d, >= 554c0a3abf216c991c5ebddcdb2c08689ecd290b < f8001e1a516ba3b495728c65b61f799cbfad6bd0, >= 4.12
Fixed versions
No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide
  1. 1
    Identify

    Confirm that Linux and an affected version are present.

  2. 2
    Prioritize

    Combine exploitation signals with asset exposure and business criticality.

  3. 3
    Remediate

    Follow the vendor advisory or supported update path and preserve rollback options.

  4. 4
    Verify

    Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
CWE
Not available
CVE-2026-64440 — Linux | SECUFOCUS NOW