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VulnerabilityPublished Updated

CVE-2026-68293: Linux kernel · net/mlx5: Fix MCIA register buffer overflow on 32 dword reads

Affects Linux kernelSource GCVE Database

0
Authoritative record:CVE-2026-68293· High 7.1

Not known to be exploited · CVSS 7.1 High · fixed in 7.0.0-38.38~24.04.4 : patch Linux kernel soon.

Data as of 26 Oct 2026, 14:05 UTC

CVSS 3.1 base score
7.1High
How severe the flaw is on the 0–10 CVSS scale.
EPSS
0.1% chance of exploitation in 30 days – higher than 3% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch
Available – fixed in 7.0.0-38.38~24.04.4, 6.8.0-1036.39, 7.0.0-38.38 +12
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Exploitation evidence

  1. Disclosed: evidence found.

    CVE published 10 Aug 2026

  2. Detectable: no evidence on record.

    No public nuclei template indexed

  3. Weaponised: no evidence on record.

    No public exploit code indexed in Metasploit or Exploit-DB

  4. Exploited in the wild: no evidence on record.

    Not in CISA KEV and no source reports exploitation

  5. Observed by OffSeq 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 to a fixed release listed under Affected software.

Affected software

ProductAffectedFixed in
Ubuntu 26.04 LTSlinuxpkg:deb/ubuntu/linux?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-38.38
Fixed in
  • 7.0.0-38.38
Ubuntu 26.04 LTSlinux-awspkg:deb/ubuntu/linux-aws?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-1014.14
Fixed in
  • 7.0.0-1014.14
Ubuntu 26.04 LTSlinux-azurepkg:deb/ubuntu/linux-azure?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-1017.17
Fixed in
  • 7.0.0-1017.17
Ubuntu 26.04 LTSlinux-azure-fdepkg:deb/ubuntu/linux-azure-fde?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-1016.16
Fixed in
  • 7.0.0-1016.16
Ubuntu 26.04 LTSlinux-gcppkg:deb/ubuntu/linux-gcp?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-1014.14
Fixed in
  • 7.0.0-1014.14
Ubuntu 26.04 LTSlinux-gkepkg:deb/ubuntu/linux-gke?arch=source&distro=resoluteOther threatsAffected
  • <7.0.0-1008.9
Fixed in
  • 7.0.0-1008.9

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: net/mlx5: Fix MCIA register buffer overflow on 32 dword reads The MCIA register can return up to 32 dwords (128 bytes) when the device advertises the mcia_32dwords capability, but struct mlx5_ifc_mcia_reg_bits only defines dword_0..11, leaving room for just 12 dwords (48 bytes) of data. mlx5_query_mcia() clamps the read size to mlx5_mcia_max_bytes() and then memcpy()s that many bytes out of the register, potentially reading past the end of the 'out' buffer. On kernels built with FORTIFY_SOURCE this is caught as a buffer overflow while reading the module EEPROM via ethtool: detected buffer overflow in memcpy kernel BUG at lib/string_helpers.c:1048! RIP: 0010:fortify_panic+0x13/0x20 Call Trace: mlx5_query_mcia.isra.0+0x200/0x210 [mlx5_core] mlx5_query_module_eeprom_by_page+0x4a/0xa0 [mlx5_core] mlx5e_get_module_eeprom_by_page+0xbb/0x120 [mlx5_core] eeprom_prepare_data+0xf3/0x170 ethnl_default_doit+0xf1/0x3b0 Extend the mcia_reg layout to 32 dwords.

References

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