---
id: CVE-2026-57192
title: >-
  Asterisk: Out-of-Bounds Write in Codec2 Decoder Due to Floor/Ceil Sample Count
  Mismatch
summary: >-
  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 cause a heap buffer
  overflow thro…
severity: medium
cvss: 6
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cvssSource: cna
cwe:
  - CWE-125
  - CWE-131
  - CWE-787
vendor: asterisk
product: asterisk
affected:
  - asterisk < 20.20.1
  - 'asterisk >= 21.0.0-pre1, < 21.12.3'
  - 'asterisk >= 22.0.0-pre1, < 22.10.1'
  - 'asterisk >= 23.0.0-pre1, < 23.4.1'
  - certified-asterisk < 20.7-cert11
  - 'certified-asterisk >= 22.8-cert1-pre1, < 22.8-cert3'
published: '2026-10-27'
updated: '2026-10-27'
sourceUpdated: '2026-10-27T21:25:40.363Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-57192'
references:
  - url: >-
      https://github.com/asterisk/asterisk/security/advisories/GHSA-qf8j-jp7h-c5hx
    label: >-
      https://github.com/asterisk/asterisk/security/advisories/GHSA-qf8j-jp7h-c5hx
  - url: >-
      https://github.com/asterisk/asterisk/commit/02e2d8d51efe1f811f2929224339cb1a35ffc079
    label: >-
      https://github.com/asterisk/asterisk/commit/02e2d8d51efe1f811f2929224339cb1a35ffc079
  - url: >-
      https://github.com/asterisk/asterisk/commit/4f5cad0611c67638a0a61cfedbe645045da8dd56
    label: >-
      https://github.com/asterisk/asterisk/commit/4f5cad0611c67638a0a61cfedbe645045da8dd56
  - url: >-
      https://github.com/asterisk/asterisk/commit/9b085d48fb66e90a0740ea59e26840421fd07acb
    label: >-
      https://github.com/asterisk/asterisk/commit/9b085d48fb66e90a0740ea59e26840421fd07acb
  - url: >-
      https://github.com/asterisk/asterisk/commit/a0bc717b2261f4df7cdecc22b58a5fffbd1aa398
    label: >-
      https://github.com/asterisk/asterisk/commit/a0bc717b2261f4df7cdecc22b58a5fffbd1aa398
  - url: >-
      https://github.com/asterisk/asterisk/commit/a2f1cc611f7d0f21faa03e8535009df3041c434c
    label: >-
      https://github.com/asterisk/asterisk/commit/a2f1cc611f7d0f21faa03e8535009df3041c434c
  - url: >-
      https://github.com/asterisk/asterisk/commit/aa40bc599a8e628859ef1c4fc944261423ceac0d
    label: >-
      https://github.com/asterisk/asterisk/commit/aa40bc599a8e628859ef1c4fc944261423ceac0d
  - url: >-
      https://github.com/asterisk/asterisk/commit/d4ccfd55ffd7cf6d73a6e5cde347a7464c301006
    label: >-
      https://github.com/asterisk/asterisk/commit/d4ccfd55ffd7cf6d73a6e5cde347a7464c301006
  - url: 'https://github.com/asterisk/asterisk/releases/tag/20.20.1'
    label: 'https://github.com/asterisk/asterisk/releases/tag/20.20.1'
  - url: 'https://github.com/asterisk/asterisk/releases/tag/21.12.3'
    label: 'https://github.com/asterisk/asterisk/releases/tag/21.12.3'
  - url: 'https://github.com/asterisk/asterisk/releases/tag/22.10.1'
    label: 'https://github.com/asterisk/asterisk/releases/tag/22.10.1'
  - url: 'https://github.com/asterisk/asterisk/releases/tag/23.4.1'
    label: 'https://github.com/asterisk/asterisk/releases/tag/23.4.1'
  - url: 'https://github.com/asterisk/asterisk/releases/tag/certified-20.7-cert11'
    label: 'https://github.com/asterisk/asterisk/releases/tag/certified-20.7-cert11'
  - url: 'https://github.com/asterisk/asterisk/releases/tag/certified-22.8-cert3'
    label: 'https://github.com/asterisk/asterisk/releases/tag/certified-22.8-cert3'
  - url: 'https://github.com/asterisk/asterisk/tree/24.0.0-pre1'
    label: 'https://github.com/asterisk/asterisk/tree/24.0.0-pre1'
tags:
  - cve.org
ingestedAt: '2026-10-27T21:58:08.857Z'
---

## Overview

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 cause a heap buffer overflow through an out-of-bounds write in the `Codec2` decoder caused by a `floor/ceil sample-count mismatch`. The `codec_codec2` module must be loaded and `Codec2` must be configured on the attacked endpoint. The attacker must pass SIP authentication by username/password or `source IP address matching`, establish a call using `Codec2`, and send carefully crafted `Codec2` audio packets. 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.

## Affected

- `asterisk < 20.20.1`
- `asterisk >= 21.0.0-pre1, < 21.12.3`
- `asterisk >= 22.0.0-pre1, < 22.10.1`
- `asterisk >= 23.0.0-pre1, < 23.4.1`
- `certified-asterisk < 20.7-cert11`
- `certified-asterisk >= 22.8-cert1-pre1, < 22.8-cert3`

## Remediation

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