Integer overflow in Linux kernel - CVE-2026-43254
Published: May 7, 2026
Vulnerability identifier: #VU130452
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-43254
CWE-ID: CWE-190
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to an integer overflow in ovpn_tcp_recv when processing coalesced TCP stream data. A remote attacker can send specially crafted TCP stream packets to cause a denial of service.
The issue occurs when large cloned socket buffers contain multiple coalesced packets, which can trigger packet drops during inner packet decapsulation.
Affected software
Linux kernel
How to mitigate CVE-2026-43254
Install security update from vendor's repository.
Linux kernel - update to 7.0 rc3