Out-of-bounds read in Linux kernel - CVE-2026-31405
Published: April 6, 2026
Vulnerability identifier: #VU124959
CSH Severity: High
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber
CVE-ID: CVE-2026-31405
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a remote attacker to execute arbitrary code.
The vulnerability exists due to an out-of-bounds read in handle_one_ule_extension() extension handler tables when processing network-controlled ULE extension header data. A remote attacker can send a specially crafted SNDU with an extension header type value of 255 to execute arbitrary code.
The out-of-bounds value may be dereferenced and called as a function pointer.
How to mitigate CVE-2026-31405
Install security update from vendor's repository.
Sources
- https://git.kernel.org/stable/c/145e50c2c700fa52b840df7bab206043997dd18e
- https://git.kernel.org/stable/c/1a6da3dbb9985d00743073a1cc1f96e59f5abc30
- https://git.kernel.org/stable/c/24d87712727a5017ad142d63940589a36cd25647
- https://git.kernel.org/stable/c/29ef43ceb121d67b87f4cbb08439e4e9e732eff8
- https://git.kernel.org/stable/c/8bde543d2a5f935ba2a6a6325a2e02f8a9256fbe
- https://git.kernel.org/stable/c/f2b65dcb78c8990e4c68a906627433be1fe38a92