CVE-2026-80791: Linux kernel · nvmet-auth: zero the AUTH_RECEIVE response buffer
Affects Linux kernelSource GCVE Database
Not known to be exploited.
Data as of 26 Oct 2026, 12:55 UTC
Rated by Threat Radar · CVSS not yet scored by NVD
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 10% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Exploitation evidence
Disclosed: evidence found.
CVE published 4 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: 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 26 Oct 2026.
What to do
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 fix is available that changes the buffer allocation from kmalloc() to kzalloc() to zero the response buffer before it is sent. Users should apply the official Linux kernel update that includes this fix. Since this is a kernel-level vulnerability, updating to the patched kernel version is the recommended remediation. Patch status is not explicitly stated in the provided data; check the official Linux kernel advisories for the exact fixed versions and update accordingly.
Description
In the Linux kernel, the following vulnerability has been resolved: nvmet-auth: zero the AUTH_RECEIVE response buffer nvmet_execute_auth_receive() allocates the response buffer with kmalloc() sized by the host-supplied AUTH_RECEIVE allocation length, but the DH-HMAC-CHAP builders write only a fixed-size message into it. The full allocation length is then copied to the wire by nvmet_copy_to_sgl(), so a remote initiator receives the bytes past the built message -- up to nearly a page of uninitialized slab -- during the pre-authentication handshake. Allocate the buffer with kzalloc() so the unwritten tail is zeroed before it is sent; conforming responses are unaffected.
References
- nvd.nist.gov/vuln/detail/CVE-2026-80791 (opens in a new tab)
- git.kernel.org/stable/c/1d6837d98bf966a041af65de5f78de7409ff83bc (opens in a new tab)
- git.kernel.org/stable/c/2dcc9226203da7275a9c29d20007da278d73d5e9 (opens in a new tab)
- git.kernel.org/stable/c/3ddcfb013322aa37eaa7a0d344b73079c38dfa21 (opens in a new tab)
- git.kernel.org/stable/c/447b668faa14710f611e714031e3739ac3ec3a4f (opens in a new tab)
- git.kernel.org/stable/c/8f6363c8d54dde95982f0ab45e77cf57ec0efd62 (opens in a new tab)
- git.kernel.org/stable/c/b26189d28442183a8b5edb754f4a6918f77ca84e (opens in a new tab)
- git.kernel.org/stable/c/dfcf013f77709ebdb282767edc2795a37cab5b57 (opens in a new tab)
- ubuntu.com/security/CVE-2026-80791 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-80791 (opens in a new tab)
- git.kernel.org/linus/3ddcfb013322aa37eaa7a0d344b73079c38dfa21 (opens in a new tab)