CVE-2026-39864: Kamailio Auth: Processing Vulnerability For Additional Authenticated User Identity Checks
Kamailio is an open source implementation of a SIP Signaling Server. Prior to 6.0.5 and 5.8.7, an out-of-bounds read in the auth module of Kamailio (formerly OpenSER and SER) allows remote attackers to cause a denial of service (process crash) via a specially crafted SIP packet if a successful user authentication without a database backend is followed by additional user identity checks. This vulnerability is fixed in 6.0.5 and 5.8.7.
Affected Software
Event History
Frequently Asked Questions
What is the severity of CVE-2026-39864?
CVE-2026-39864 has a high severity rating due to the potential for remote code execution through an out-of-bounds read vulnerability.
How do I fix CVE-2026-39864?
To fix CVE-2026-39864, upgrade Kamailio to version 6.0.6 or 5.8.8 or later, where the vulnerability has been addressed.
What versions of Kamailio are affected by CVE-2026-39864?
CVE-2026-39864 affects Kamailio versions prior to 6.0.5 and 5.8.7.
Can CVE-2026-39864 be exploited remotely?
Yes, CVE-2026-39864 can be exploited remotely by attackers to execute unauthorized actions.
Is there a mitigation for CVE-2026-39864 if I cannot upgrade?
If you cannot upgrade, implementing strict access controls and monitoring for unusual activity can serve as temporary mitigations for CVE-2026-39864.