CVE-2026-53524

Published: Aug 21, 2026Modified: Aug 24, 2026

6.5

Vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Exploitability: 2.8 / Impact: 3.6

Source: security-advisories@github.com (Secondary)

Description

WeeChat (Wee Enhanced Environment for Chat) is a free chat client. In versions 4.3.0 through 4.9.0, the WeeChat relay module's WebSocket permessage-deflate decompression function relay_websocket_inflate() has no upper bound on output size. An authenticated relay user can send a small compressed WebSocket frame (~100 bytes) that decompresses to gigabytes, exhausting all server memory and crashing the entire WeeChat process. The api protocol enables permessage-deflate and requires authentication before WebSocket upgrade. Version 4.9.1 patches the issue.

Related CWEs

CWE-409

Improper Handling of Highly Compressed Data (Data Amplification)

The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.

References (2)

https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3

Source: security-advisories@github.com

https://github.com/weechat/weechat/security/advisories/GHSA-v2v4-45wm-5cr3

Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0

Timeline

No history available yet.