CVE-2026-39863

HIGH

Kamailio Core: TCP Data Processing Vulnerability

Title source: cna
STIX 2.1

Description

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.

References (1)

Core 1
Core References

Scores

CVSS v3 7.5
EPSS 0.0045
EPSS Percentile 35.8%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-119
Status published
Products (4)
kamailio/kamailio 6.1.0
kamailio/kamailio < 5.8.8 (2 CPE variants)
kamailio/kamailio >= 6.0.0, < 6.0.6
kamailio/kamailio >= 6.1.0, < 6.1.1
Published Apr 08, 2026
Tracked Since Apr 09, 2026