WeeChat :: documentation

WeeChat

Overview: 1 vulnerability

WSA	Score	Severity	Issue	Vulnerability type	Scope	Versions	Fix	Release date
WSA-2026-20	7.5		Missing size limit of data queued for sending to clients.	Memory Allocation with Excessive Size Value	Relay	0.3.9 → 4.10.0	4.10.1	Sep 5, 2026

WSA-2026-20: [Relay] Missing size limit of data queued for sending to clients.

Vulnerability

CVE

Not available

CVSS vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (detail)

CVSS score

7.5 / 10

Severity

high

Vulnerability type

Memory Allocation with Excessive Size Value (detail)

Scope

Relay

Affected versions

0.3.9 → 4.10.0

Fixed version

4.10.1 (Sep 5, 2026) - ChangeLog

Tracker

issue #2357

Commits

Description

When queuing data of sending to clients, the Relay plugin builds a partial buffer.
There is no limit for the allocated buffer.
A malicious unauthenticated client sending PING control frames can can lead to memory exhaustion and the WeeChat process can be killed by the OOM killer.

Mitigation

Unload relay plugin with command: /plugin unload relay and see: /help weechat.plugin.autoload.

Credit

The issue was discovered by Acts1631.