An integer overflow can happen when looping over items in a list.
This can only happen in rare conditions on 32 and 64-bit systems, as the list must contain more than 2,147,483,647 elements.
On 16-bit systems, this happens with a list that contains more than 32,767 elements.
Mitigation
There is no known mitigation.
The upgrade to the latest stable version is highly recommended.
Credit
The issue was discovered by Yiheng Cao.
WSA-2022-1: [IRC, Plugins] Possible man-in-the-middle attack in TLS connection to servers.
After changing the options weechat.network.gnutls_ca_system or weechat.network.gnutls_ca_user, the TLS verification function is lost.
Consequently, any connection to a server with TLS is made without verifying the certificate, which could lead to a man-in-the-middle attack.
Connection to IRC servers with TLS is affected, as well as any connection a server made by a plugin or a script using the function hook_connect.
Mitigation
After changing options weechat.network.gnutls_ca_system or weechat.network.gnutls_ca_user, you must restart WeeChat.
WSA-2021-1: [Relay] Crash on malformed websocket frame in relay plugin.
A crash happens when decoding a malformed websocket frame in relay plugin.
This happens even if a password is set in relay plugin, the malformed websocket frame can be received before the authentication of the client.
Mitigation
There are multiple ways to mitigate this issue:
Rremove all relays, see: /help relay
Unload relay plugin with command: /plugin unload relay and see: /help weechat.plugin.autoload
Secure relay to allow only some trusted IP addresses, see: /help relay.network.allowed_ips