CVE-2026-64319: Linux kernel · nvmet-auth: validate reply message payload bounds against transfer length
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 9.1 Critical · fixed in 6.8.0-147.147 : patch Linux kernel as a priority.
Data as of 6 Nov 2026, 17:27 UTC
Thin evidence
One scorer or none| CNA (Linux) | CVSS 3.1 | 9.1 |
|---|
- Patch
- Available – fixed in 6.8.0-147.147, 6.8.0-1067.70, 7.0.0-1012.12~24.04.1 +30
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Jul 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: 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 6 Nov 2026.
What to do
Upgrade to a fixed release listed under Affected software.
Patches and advisories
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)
Affected software
| Product | Affected | Fixed in |
|---|---|---|
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
A patch is available and should be applied promptly. The vulnerability has been fixed by adding proper bounds validation in the Linux kernel nvmet-auth module. Users should update to one of the fixed kernel versions including 6.8.0-147.147, 6.8.0-1067.70, 7.0.0-1012.12~24.04.1, and others listed in the established facts. No additional mitigations are indicated by the vendor advisory.
Description
A critical vulnerability in the Linux kernel's nvmet-auth module allows an attacker to cause out-of-bounds heap reads by sending a crafted DHCHAP_REPLY message with manipulated hash length and DH value length fields. This flaw occurs because the kernel does not properly validate these lengths against the allocated buffer size before accessing variable-length arrays. The vulnerability is exploitable pre-authentication and can lead to information disclosure and denial of service. Multiple Linux kernel versions prior to fixed releases are affected. A patch correcting the bounds validation has been released.
References
- ubuntu.com/security/CVE-2026-64319 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-64319 (opens in a new tab)
- git.kernel.org/linus/3a413ece2504c70aa34a20be4dafec04e8c741f9 (opens in a new tab)
- git.kernel.org/stable/c/3a413ece2504c70aa34a20be4dafec04e8c741f9 (opens in a new tab)
- git.kernel.org/stable/c/6d7649c1231dac14d906985d2936967e23041c26 (opens in a new tab)
- git.kernel.org/stable/c/80cd28b56ab62d3e7ed0a7bf05282e6d3ee5b2a0 (opens in a new tab)
- git.kernel.org/stable/c/999f6205ede984a786f35f727b01f971b98e215d (opens in a new tab)
- git.kernel.org/stable/c/caa71b3a43ea5c13fe7141cb019ebcb03b8ac857 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8727-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8781-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-3 (opens in a new tab)
- ubuntu.com/security/notices/USN-8800-1 (opens in a new tab)
- ubuntu.com/security/notices/USN-8760-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-2 (opens in a new tab)
- ubuntu.com/security/notices/USN-8726-4 (opens in a new tab)
- ubuntu.com/security/notices/USN-8728-3 (opens in a new tab)