CVE-2026-62963 HIGH

CVE-2026-62963: Centrifugo: Decompression bomb DoS via permessage-deflate in unidirectional WebSocket transport

Vendor Centrifugal
Product centrifugo
Weakness CWE-409
Published July 16, 2026
Last update July 16, 2026
View on NVD All CVEs

CVSS base score

8.7/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

What the vulnerability does

01Description

Centrifugo is an open-source scalable real-time messaging server. Prior to 6.8.4, Centrifugo unidirectional WebSocket transport with uni_websocket.compression enabled enforced uni_websocket.message_size_limit against compressed wire-frame length in internal/websocket/conn.go advanceFrame, but ReadMessage used io.ReadAll after decompression without an output cap, allowing unauthenticated requests to /connection/uni_websocket to trigger large memory and CPU consumption. This issue is fixed in version 6.8.4.

Key dates

02Disclosure timeline

July 16, 2026 CVE published