---
id: CVE-2026-106804
title: >-
  A stack-based buffer overflow exists in Kamailio v6.1.3 and v6.1.4 in the
  ims_qos_npn module
summary: >-
  A stack-based buffer overflow exists in Kamailio v6.1.3 and v6.1.4 in the
  ims_qos_npn module. The w_rx_aar_register() function copies the
  attacker-controlled host field from the SIP `Via` header into a fixed 46-byte
  stack buffer without …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: adp
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-11-02T18:54:35.760686Z'
exploitAvailable: true
published: '2026-11-02'
updated: '2026-11-02'
sourceUpdated: '2026-11-02T18:55:18.235Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-106804'
references:
  - url: 'https://github.com/kamailio/kamailio/issues/4953'
  - url: 'https://gist.github.com/hackeryounow/f5af75502ea6df600428c46bb9bbf39e'
tags:
  - cve.org
  - exploit-available
epss: 0.00573
epssPercentile: 0.47567
ingestedAt: '2026-11-05T19:30:42.780Z'
---

## Overview

A stack-based buffer overflow exists in Kamailio v6.1.3 and v6.1.4 in the ims_qos_npn module. The w_rx_aar_register() function copies the attacker-controlled host field from the SIP `Via` header into a fixed 46-byte stack buffer without validating its length. An unauthenticated remote attacker can trigger the vulnerability with a crafted SIP `REGISTER` request, causing stack corruption and termination of the affected Kamailio instance, resulting in denial of service.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.