SB20251210125 - Improper locking in Linux kernel l2tp
Published: December 10, 2025 Updated: December 12, 2025
Security Bulletin ID
SB20251210125
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 security vulnerability.
1) Improper locking (CVE-ID: CVE-2023-53809)
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper locking within the pppol2tp_tunnel_mtu() and pppol2tp_connect() functions in net/l2tp/l2tp_ppp.c. A local user can perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/4a413d360959962995e16a899cf2b9ef53e9fcb9
- https://git.kernel.org/stable/c/4bb736b40475528ac1aa8c98b368563618488a70
- https://git.kernel.org/stable/c/5370647dd745bb3d8f37057006be207ddd8e9314
- https://git.kernel.org/stable/c/9ca5e7ecab064f1f47da07f7c1ddf40e4bc0e5ac
- https://git.kernel.org/stable/c/f6df58aa15f7d469f69b1dd21b001ff483255244
- https://mirrors.edge.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.15.99