CVE-2026-64440

Kernel memory corruption via oversized Wi-Fi response

Published Jul 25, 2026 · Updated Jul 25, 2026

Out-of-bounds write in Linux Kernel 4.12 and later allows physically proximate attackers to corrupt kernel memory via a crafted Wi-Fi response. In rtl8723bs HT_caps_handler(), the driver copies an unvalidated 802.11 AssocResponse length into a fixed 26-byte array, letting up to 229 bytes overwrite adjacent mlme_ext_info fields. Exploitation requires a system using the rtl8723bs wireless driver to associate with a malicious access point; no specific crash or code-execution outcome is published.

CVSS severity8.1
High
EPSS probability0.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Out-of-bounds write in Linux Kernel 4.12 and later allows physically proximate attackers to corrupt kernel memory via a crafted Wi-Fi response. In rtl8723bs HT_caps_handler(), the driver copies an unvalidated 802.11 AssocResponse length into a fixed 26-byte array, letting up to 229 bytes overwrite adjacent mlme_ext_info fields. Exploitation requires a system using the rtl8723bs wireless driver to associate with a malicious access point; no specific crash or code-execution outcome is published.

The record

CVE
CVE-2026-64440
Published
Jul 25, 2026
Updated
Jul 25, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 25, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 25, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.12
  2. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d
  3. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <37f642d47c3648a707df3ceb092eee1adffbfd28
  4. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <6f91621fc45025ad3c0be796b70e6e4cee22fc69
  5. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <8c872b47c7fc32e95e0da1db7512388794adcd69
  6. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <918537a0fbed85aab61fa28ad75e6279070610c9
  7. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a
  8. Affected versionversion=554c0a3abf216c991c5ebddcdb2c08689ecd290b <f8001e1a516ba3b495728c65b61f799cbfad6bd0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.12; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <225b6d3fc7e99ac3d20b6c861d1e47d24e7ea31d; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <37f642d47c3648a707df3ceb092eee1adffbfd28; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <6f91621fc45025ad3c0be796b70e6e4cee22fc69; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <8c872b47c7fc32e95e0da1db7512388794adcd69; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <918537a0fbed85aab61fa28ad75e6279070610c9; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <bb3b942da4123b55d1cacf19d1a7d5ba15dbf83a; version=554c0a3abf216c991c5ebddcdb2c08689ecd290b <f8001e1a516ba3b495728c65b61f799cbfad6bd0

Published CVSS scores

8.1kernel.orgCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo