CVE-2026-39863 PUBLISHED

Kamailio Core: TCP Data Processing Vulnerability

Assigner: GitHub_M
Reserved: 07.04.2026 Published: 08.04.2026 Updated: 08.04.2026

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.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS Score: 7.5

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	None
Privileges Required	None	Integrity Impact	None
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	kamailio
Product	kamailio
Versions	Version < 5.8.8 is affected Version >= 6.0.0, < 6.0.6 is affected Version >= 6.1.0, < 6.1.1 is affected

References

https://github.com/kamailio/kamailio/security/advisories/GHSA-2wj4-f825-2h2f

Problem Types

CWE-119: Improper Restriction of Operations within the Bounds of a Memory Buffer CWE