CVE-2026-39863 HIGH

CVE-2026-39863: Kamailio Core: TCP Data Processing Vulnerability

Vendor Kamailio
Product kamailio
Weakness CWE-119
Published April 8, 2026
Last update April 9, 2026

CVSS base score

7.5/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality None
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

What the vulnerability does

01Description

Kamailio is an open source implementation of a SIP Signaling Server. Prior to 6.1.1, 6.0.6, and 5.8.8, an out-of-bounds access in the core of Kamailio (formerly OpenSER and SER) allows remote attackers to cause a denial of service (process crash) via a specially crafted data packet sent over TCP. The issue impacts Kamailio instances having TCP or TLS listeners. This vulnerability is fixed in 5.1.1, 6.0.6, and 5.8.8.

Key dates

02Disclosure timeline

April 8, 2026 CVE published
April 9, 2026 Record updated