---
id: "CVE-2026-57185"
kind: "vulnerability"
aliases: ["CVE-2026-57185"]
title: "Asterisk: crafted SIP NOTIFY crashes PBX via buffer over-read"
severity: "medium"
cvss: 6.5
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["asterisk", "package", "pbx", "pjsip", "self-hosted", "voip"]
not_affected_if: ["auth-required", "no-pjsip"]
published_at: "2026-10-27T17:17:01+00:00"
first_seen_at: "2026-10-27T17:32:46+00:00"
updated_at: "2026-10-27T17:34:46+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-57185", "first_seen_at": "2026-10-27T17:32:46+00:00"}]
---

# Asterisk: crafted SIP NOTIFY crashes PBX via buffer over-read

Asterisk's PJSIP MWI body parser reads past the end of a buffer when handling a crafted SIP NOTIFY request. An authenticated attacker can crash the Asterisk process, causing a denial of service.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Run `asterisk -V` and compare against the fixed versions: 20.20.1, 21.12.3, 22.10.1, 23.4.1, or Certified Asterisk 20.7-cert11 and 22.8-cert3.
- Check that PJSIP is in use (`pjsip show endpoints`); the MWI body parser is part of the PJSIP channel driver.

## Fix

- Upgrade Asterisk to `20.20.1`, `21.12.3`, `22.10.1` or `23.4.1`, or Certified Asterisk to `20.7-cert11` or `22.8-cert3`, matching your release line.

## Timeline

- 2026-10-27T17:32:46+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-57185

## From the sources

Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, an authenticated attacker may crash Asterisk through a buffer over-read in the `PJSIP MWI body parser` by sending a carefully crafted `SIP NOTIFY` request. The attacker must pass SIP authentication using either a username/password or `source IP address matching`. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.

---

_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_