A malicious or compromised IRC server could send data with no end-of-line (or a flood of "005" messages), making WeeChat accumulate it in a buffer that grew without limit, until all memory was exhausted. The unterminated received message and the accumulated "005" (ISUPPORT) data are now bounded by IRC_SERVER_RECV_MSG_MAX_LENGTH and IRC_SERVER_ISUPPORT_MAX_LENGTH: extra data is ignored once the limit is reached.
WeeChat
WeeChat (Wee Enhanced Environment for Chat) is a free chat client, fast and light, designed for many operating systems.
It is highly customizable and extensible with scripts.
Homepage: https://weechat.org/
Features
- Modular chat client: WeeChat has a lightweight core and optional plugins. All plugins (including IRC) are independent and can be unloaded.
- Multi-platform: WeeChat runs on GNU/Linux, *BSD, GNU/Hurd, Haiku, macOS and Windows (WSL and Cygwin).
- Multi-protocol: WeeChat is designed to support multiple protocols via plugins, like IRC.
- Standards-compliant: the IRC plugin is compliant with RFCs 1459, 2810, 2811, 2812, 2813 and 7194.
- Small, fast, and very light: the core is and should stay as light and fast as possible.
- Customizable and extensible: there are a lot of options to customize WeeChat, and it is extensible with C plugins and scripts (Perl, Python, Ruby, Lua, Tcl, Scheme, JavaScript and PHP).
- Fully documented: there is comprehensive documentation, which is translated into several languages.
- Developed from scratch: WeeChat was built from scratch and is not based on any other client.
- Free software: WeeChat is released under GPLv3.
On WeeChat's website you can find more screenshots.
Installation
WeeChat can be installed using your favorite package manager (recommended) or by compiling it yourself.
For detailed instructions, please check the WeeChat user's guide.
Semantic versioning
WeeChat follows "practical" semantic versioning; see CONTRIBUTING.md.
Copyright
Copyright © 2003-2026 Sébastien Helleu
This file is part of WeeChat, the extensible chat client.
WeeChat is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version.
WeeChat is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with WeeChat. If not, see https://www.gnu.org/licenses/.

