4.4
MEDIUM CVSS 3.1
CVE-2026-39864
Kamailio Auth: Processing Vulnerability For Additional Authenticated User Identity Checks
Description

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.

INFO

Published Date :

April 8, 2026, 8:16 p.m.

Last Modified :

April 8, 2026, 9:26 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-39864 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Kamailio to a fixed version to prevent crashes from crafted SIP packets.
  • Update Kamailio to version 6.0.5 or 5.8.7.
  • Apply relevant security patches for your Kamailio version.
  • Restart the Kamailio service after updating.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-39864.

URL Resource
https://github.com/kamailio/kamailio/security/advisories/GHSA-6m86-m342-g48m
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-39864 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-39864 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-39864 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-39864 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Apr. 08, 2026

    Action Type Old Value New Value
    Added Description 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.
    Added CVSS V3.1 AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-125
    Added Reference https://github.com/kamailio/kamailio/security/advisories/GHSA-6m86-m342-g48m
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.