SB20260507276 - Integer overflow in Linux kernel l2tp
Published: May 7, 2026
Security Bulletin ID
SB20260507276
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Integer overflow (CVE-ID: CVE-2026-43080)
CWE-ID: CWE-190 - Integer overflow
CVSSv4: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a local user to cause a denial of service.
The vulnerability exists due to an integer overflow in l2tp_xmit_core when processing oversized PPPoL2TP packets with UDP encapsulation. A local user can send an oversized packet to trigger a kernel warning and cause a denial of service.
The issue occurs because the UDP length field is 16-bit and the oversized length value is truncated.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/77c1489398c85a844f90205f5e76fd6bc8bb4089
- https://git.kernel.org/stable/c/86534c97abd6365a9a021fd767a2023e63c44469
- https://git.kernel.org/stable/c/9ccce02d501335f59a02f26c878c5e095b16302f
- https://git.kernel.org/stable/c/ebe560ea5f54134279356703e73b7f867c89db13
- https://git.kernel.org/stable/c/f295fe86e22ff0a2ecebf05e30a387e5cf6f6ddc