---
id: CVE-2026-45705
title: OpenSIPS is a Session Initiation Protocol (SIP) server implementation
summary: >-
  OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In
  versions prior to 3.6.6 and 4.0.0-rc1, the find_line_delimiter() function in
  the multipart body parser performs an out-of-bounds read via strncmp() when
  searching …
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-125
published: '2026-08-05'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T20:41:31.497'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-45705'
references:
  - url: >-
      https://github.com/OpenSIPS/opensips/commit/4d23613b65579b073784a07a65d3bf52443a4efb
    label: security-advisories@github.com
  - url: >-
      https://github.com/OpenSIPS/opensips/commit/5f103effaf5f372cccffe0b138f16998eba12668
    label: security-advisories@github.com
  - url: >-
      https://github.com/OpenSIPS/opensips/security/advisories/GHSA-chxf-9368-fqcp
    label: security-advisories@github.com
  - url: >-
      https://github.com/OpenSIPS/opensips/security/advisories/GHSA-chxf-9368-fqcp
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
epss: 0.00292
epssPercentile: 0.22003
ingestedAt: '2026-09-08T21:11:12.267Z'
---

## Overview

OpenSIPS is a Session Initiation Protocol (SIP) server implementation. In versions prior to 3.6.6 and 4.0.0-rc1, the find_line_delimiter() function in the multipart body parser performs an out-of-bounds read via strncmp() when searching for MIME boundary delimiters. After finding a -- pattern near the end of the body, the function compares delimiter.len bytes (typically 20-70) starting from a position at or past the logical end of the body buffer, reading past the body boundary. The bug triggers when a SIP message has Content-Type: multipart/mixed with a boundary parameter and its body contains -- within two to three bytes of the body's end without being followed by the actual boundary delimiter. This issue has been fixed in versions 3.6.6 and 4.0.0-rc1.

## Remediation

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