CVE-2026-80584: Linux kernel · s390/qeth: validate user buffer length in SNMP and ARP query ioctls
Affects Linux kernelSource GCVE Database
Not known to be exploited · CVSS 8.4 High : upgrade to 6.8.0-1036.39 soon.
Data as of 28 Oct 2026, 01:00 UTC
- Patch
- Available – fixed in 6.8.0-1036.39
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 26 Aug 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
Upgrade the Ubuntu linux-nvidia-tegra package to 6.8.0-1036.39.
Patches and advisories
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.
Description
In the Linux kernel, the following vulnerability has been resolved: s390/qeth: validate user buffer length in SNMP and ARP query ioctls qeth_snmp_command() and qeth_l3_arp_query() allocate a buffer sized by a user-supplied length (udata_len) without checking a lower bound, then set udata_offset to a fixed non-zero value and pass both to a reply callback. The callback bounds-checks the copy with if ((udata_len - udata_offset) < len) Both fields are u32, so a udata_len smaller than udata_offset makes the subtraction wrap and the check pass, and the following memcpy() writes past the allocation. A udata_len of 0 also yields ZERO_SIZE_PTR from kzalloc(), which the existing NULL check does not catch. Reject buffers smaller than udata_offset before allocating, so the callback subtraction can no longer underflow.
References
- ubuntu.com/security/CVE-2026-80584 (opens in a new tab)
- cve.org/CVERecord?id=CVE-2026-80584 (opens in a new tab)
- git.kernel.org/stable/c/3083818e67bcd656965797fbac9a3d6c1d44f78a (opens in a new tab)
- git.kernel.org/stable/c/91935843f9396a9e45253e2c0d4337ca1371754b (opens in a new tab)
- git.kernel.org/stable/c/75fb3151513d7d9f77a8f9545418279b119c06b8 (opens in a new tab)
- git.kernel.org/stable/c/9d00eeb2d27f4cc817c5e408760226d43f811ec6 (opens in a new tab)
- git.kernel.org/stable/c/a3083647747942ea32faf14560d6397ff3068046 (opens in a new tab)
- git.kernel.org/stable/c/d141f087b1af656f055d7c5793a3e87817ba0bbe (opens in a new tab)
- git.kernel.org/stable/c/46443eaddebd84c51940857b11787229be169dec (opens in a new tab)
- git.kernel.org/stable/c/cc423f4105fe145b33e1d7cad34245a798358f73 (opens in a new tab)
- ubuntu.com/security/notices/USN-8886-1 (opens in a new tab)