SB20261022184 - Race condition in Linux kernel net ovpn driver

Description

This security bulletin contains information about 1 vulnerability.

1) Race condition (CVE-ID: CVE-2026-98604)

CWE-ID: CWE-362 - Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')

CVSSv4: 6.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]

The vulnerability allows a remote attacker to cause inconsistent local endpoint address reads and potentially disrupt VPN traffic.

The vulnerability exists due to a race condition in the Linux kernel ovpn driver's local endpoint learning when updating a shared bind address concurrently with UDP transmission. A remote attacker can send traffic that triggers local endpoint learning during transmission to cause a torn IPv6 address read, potentially disrupting VPN traffic.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/21dbc9f4d0bdd3b22f91beabc7840064bf11594f
• https://git.kernel.org/stable/c/aea934a221ec6a867221e5b765f65f1857befd53
• https://git.kernel.org/stable/c/e283009151d3d131447c2edda500199c5fda5f72