MEDIUM · 4.7

CVE-2023-53020

In the Linux kernel, the following vulnerability has been resolved: l2tp: close all race conditions in l2tp_tunnel_register() The code in l2tp_tunnel_register() is racy in several ways: 1. It modif...

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: l2tp: close all race conditions in l2tp_tunnel_register() The code in l2tp_tunnel_register() is racy in several ways: 1. It modifies the tunnel socket _after_ publishing it. 2. It calls setup_udp_tunnel_sock() on an existing socket without locking. 3. It changes sock lock class on fly, which triggers many syzbot reports. This patch amends all of them by moving socket initialization code before publishing and under sock lock. As suggested by Jakub, the l2tp lockdep class is not necessary as we can just switch to bh_lock_sock_nested().

CVSS Score

4.7

MEDIUM

CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack Vector
LOCAL
Attack Complexity
HIGH
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH

Affected Products

VendorProductVersions
LinuxLinux Kernel>= 3.6, < 5.10.166

Related Weaknesses (CWE)

References

FAQ

What is CVE-2023-53020?

CVE-2023-53020 is a vulnerability with a CVSS score of 4.7 (MEDIUM). In the Linux kernel, the following vulnerability has been resolved: l2tp: close all race conditions in l2tp_tunnel_register() The code in l2tp_tunnel_register() is racy in several ways: 1. It modif...

How severe is CVE-2023-53020?

CVE-2023-53020 has been rated MEDIUM with a CVSS base score of 4.7/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2023-53020?

Check the references section above for vendor advisories and patch information. Affected products include: Linux Linux Kernel.