Integer overflow happens in conversion of a version as string to an integer number, if the version is greater than 0x7FFFFFFF (127.255.255.255), so if the version is at least 0x80000000 (128.0.0.0).
Mitigation
There is no known mitigation.
The upgrade to the latest stable version is highly recommended.
WSA-2025-2: [Core] Integer overflow in base32 decode/encode functions.
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-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