# CVE-2021-40516: weechat: WeeChat before 3.2.1 allows remote attackers to cause a denial of service (crash) via a crafted WebSocket frame that...

CVE-2021-40516 is fixed in 12 products on 1 platform, first by weechat 1.9.1-1ubuntu1+esm1, released September 5, 2021. It is not reported as exploited. Patch Radar priority: Routine.

- Web page: https://patchblox.com/security/cve/CVE-2021-40516
- Priority: Routine
- CVSS: n/a (Medium)
- EPSS: 0.0159
- CISA KEV: not listed
- Exploited (vendor report): no
- Publicly disclosed: no
- Published: Sep 5, 2021

## Description

WeeChat before 3.2.1 allows remote attackers to cause a denial of service (crash) via a crafted WebSocket frame that trigger an out-of-bounds read in plugins/relay/relay-websocket.c in the Relay plugin.

## Where it's fixed

| Platform | Product | Fixed in | Fix | Released |
|---|---|---|---|---|
| Linux | weechat Ubuntu 18.04.6 LTS (bionic) | 1.9.1-1ubuntu1+esm1 | [weechat 1.9.1-1ubuntu1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-weechat-1.9.1-1ubuntu1-esm1.md) | Sep 5, 2021 |
| Linux | weechat Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-core Ubuntu 18.04.6 LTS (bionic) | 1.9.1-1ubuntu1+esm1 | [weechat-core 1.9.1-1ubuntu1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-weechat-core-1.9.1-1ubuntu1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-core Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-core 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-core-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-curses Ubuntu 18.04.6 LTS (bionic) | 1.9.1-1ubuntu1+esm1 | [weechat-curses 1.9.1-1ubuntu1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-weechat-curses-1.9.1-1ubuntu1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-curses Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-curses 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-curses-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-guile Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-guile 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-guile-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-headless Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-headless 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-headless-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-lua Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-lua 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-lua-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-perl Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-perl 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-perl-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-php Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-php 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-php-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-plugins Ubuntu 18.04.6 LTS (bionic) | 1.9.1-1ubuntu1+esm1 | [weechat-plugins 1.9.1-1ubuntu1+esm1](https://patchblox.com/security/data/fix/linux/ubuntu-bionic-weechat-plugins-1.9.1-1ubuntu1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-plugins Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-plugins 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-plugins-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-python Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-python 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-python-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-ruby Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-ruby 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-ruby-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |
| Linux | weechat-tcl Ubuntu 20.04 LTS (focal) | 2.8-1ubuntu0.1~esm1 | [weechat-tcl 2.8-1ubuntu0.1~esm1](https://patchblox.com/security/data/fix/linux/ubuntu-focal-weechat-tcl-2.8-1ubuntu0.1-esm1.md) | Sep 5, 2021 |

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