CVE-2026-64539

Kernel memory corruption via oversized advertising data

Published Jul 27, 2026 · Updated Jul 27, 2026

Stack out-of-bounds write in Linux Kernel 4.1 and later allows local users to corrupt kernel memory through Bluetooth advertising data. The eir_create_adv_data() function prepends a three-byte Flags structure and then copies user-supplied instance data into a 31-byte legacy advertising buffer without checking the combined length. Exploitation requires CAP_NET_ADMIN, an LE-only controller, and the legacy advertising path; the record demonstrates kernel-stack corruption but does not document reliable privilege escalation.

CVSS severity7.8
High
EPSS probability0.12%
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

Stack out-of-bounds write in Linux Kernel 4.1 and later allows local users to corrupt kernel memory through Bluetooth advertising data. The eir_create_adv_data() function prepends a three-byte Flags structure and then copies user-supplied instance data into a 31-byte legacy advertising buffer without checking the combined length. Exploitation requires CAP_NET_ADMIN, an LE-only controller, and the legacy advertising path; the record demonstrates kernel-stack corruption but does not document reliable privilege escalation.

The record

CVE
CVE-2026-64539
Published
Jul 27, 2026
Updated
Jul 27, 2026
Vendor
The Linux Kernel Organization
Product
Linux Kernel
Classifications
Unavailable
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 27, 2026CVE publishedPublication date reported by the CVE source.
  2. Jul 27, 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=4.1
  2. Affected versionversion=b44133ff03be30b55f23036e62f403a3f7784fce <09301f1fdf2aef8cce34d0c4650c30e7edb1ced9
  3. Affected versionversion=b44133ff03be30b55f23036e62f403a3f7784fce <0f0b6232af56441d0a2dcb173cc4f8d8aab39014
  4. Affected versionversion=b44133ff03be30b55f23036e62f403a3f7784fce <57077eeb586c42f124bc09e018449362223067b3
  5. Affected versionversion=b44133ff03be30b55f23036e62f403a3f7784fce <6f5fb689fdf80bdd143f22a502f9eb1f3c85e286
  6. Affected versionversion=b44133ff03be30b55f23036e62f403a3f7784fce <f1b4df9c260c51726da2e86e19322825fddeefd0

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

The Linux Kernel Organization · Linux Kernelversion=4.1; version=b44133ff03be30b55f23036e62f403a3f7784fce <09301f1fdf2aef8cce34d0c4650c30e7edb1ced9; version=b44133ff03be30b55f23036e62f403a3f7784fce <0f0b6232af56441d0a2dcb173cc4f8d8aab39014; version=b44133ff03be30b55f23036e62f403a3f7784fce <57077eeb586c42f124bc09e018449362223067b3; version=b44133ff03be30b55f23036e62f403a3f7784fce <6f5fb689fdf80bdd143f22a502f9eb1f3c85e286; version=b44133ff03be30b55f23036e62f403a3f7784fce <f1b4df9c260c51726da2e86e19322825fddeefd0

Published CVSS scores

7.8kernel.orgCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
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