# CVE-2026-26203: asterisk: PJSIP is a free and open source multimedia communication library

CVE-2026-26203 is fixed in asterisk on 1 platform by DEBIAN-CVE-2026-26203 (version 1:22.10.0+dfsg+~cs6.17.60671434-1), released February 19, 2026. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2026-26203
- Priority: Routine
- CVSS: 6.5 (medium)
- EPSS: 0.0012
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Feb 19, 2026

## Description

PJSIP is a free and open source multimedia communication library. Versions prior to 2.17 have a critical heap buffer underflow vulnerability in PJSIP's H.264 packetizer. The bug occurs when processing malformed H.264 bitstreams without NAL unit start codes, where the packetizer performs unchecked pointer arithmetic that can read from memory located before the allocated buffer. Version 2.17 contains a patch for the issue.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | asterisk Debian 14 | 1:22.10.0+dfsg+~cs6.17.60671434-1 | [DEBIAN-CVE-2026-26203](https://patchblox.com/security/data/fix/linux/debian-cve-2026-26203.md) | Feb 19, 2026 |

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Data as of 2026-11-09T01:18:40Z UTC. Source: Patchblox Patch Radar (https://patchblox.com/security/patch-radar). Patchblox finds out-of-date software on Windows, macOS and Linux and updates it through release rings: https://patchblox.com/demo

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