# CVE-2021-43845: ring: PJSIP is a free and open source multimedia communication library

CVE-2021-43845 is fixed in 5 products on 1 platform, first by DEBIAN-CVE-2021-43845, released December 27, 2021. It is not reported as exploited. Patch Radar priority: Urgent.

- Web page: https://patchblox.com/security/cve/CVE-2021-43845
- Priority: Urgent
- CVSS: 9.1 (critical)
- EPSS: 0.0389
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Dec 27, 2021

## Description

PJSIP is a free and open source multimedia communication library. In version 2.11.1 and prior, if incoming RTCP XR message contain block, the data field is not checked against the received packet size, potentially resulting in an out-of-bound read access. This affects all users that use PJMEDIA and RTCP XR. A malicious actor can send a RTCP XR message with an invalid packet size.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | asterisk Debian 14 | 1:18.12.0~dfsg+~cs6.12.40431413-1 | [DEBIAN-CVE-2021-43845](https://patchblox.com/security/data/fix/linux/debian-cve-2021-43845.md) | Dec 27, 2021 |
| Linux | jami Ubuntu 20.04 LTS (focal) | 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1 | [jami 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-jami-20190215.1.f152c98-ds1-1-deb10u2build0.20.04.1.md) | Mar 14, 2023 |
| Linux | jami-daemon Ubuntu 20.04 LTS (focal) | 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1 | [jami-daemon 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-jami-daemon-20190215.1.f152c98-ds1-1-deb10u2build0.20.04.1.md) | Mar 14, 2023 |
| Linux | ring Debian 12.15 (bookworm) | 20230206.0~ds1-1 | [DEBIAN-CVE-2021-43845](https://patchblox.com/security/data/fix/linux/debian-cve-2021-43845.md) | Dec 27, 2021 |
| Linux | ring Ubuntu 18.04.6 LTS (bionic) | 20180228.1.503da2b~ds1-1ubuntu0.1~esm1 | [ring 20180228.1.503da2b~ds1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ring-20180228.1.503da2b-ds1-1ubuntu0.1-esm1.md) | Mar 14, 2023 |
| Linux | ring Ubuntu 20.04 LTS (focal) | 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1 | [ring 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ring-20190215.1.f152c98-ds1-1-deb10u2build0.20.04.1.md) | Mar 14, 2023 |
| Linux | ring-daemon Ubuntu 18.04.6 LTS (bionic) | 20180228.1.503da2b~ds1-1ubuntu0.1~esm1 | [ring-daemon 20180228.1.503da2b~ds1-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-ring-daemon-20180228.1.503da2b-ds1-1ubuntu0.1-esm1.md) | Mar 14, 2023 |
| Linux | ring-daemon Ubuntu 20.04 LTS (focal) | 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1 | [ring-daemon 20190215.1.f152c98~ds1-1+deb10u2build0.20.04.1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-ring-daemon-20190215.1.f152c98-ds1-1-deb10u2build0.20.04.1.md) | Mar 14, 2023 |

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Data as of 2026-11-08T06:59:42Z 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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