CVE-2026-53524 (GCVE-0-2026-53524)

Vulnerability from cvelistv5 – Published: 2026-08-21 22:18 – Updated: 2026-08-24 20:09
VLAI
Title
WeeChat has a Decompression Bomb in Relay WebSocket (DoS)
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-24 20:09 UTC
CWE
  • CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7745 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
weechat weechat Affected: >= 4.3.0, < 4.9.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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