CVE-2026-62963

Description

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.

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Weakness Type (CWE)

CWE-409 CWE-409

References

Other References

https://github.com/centrifugal/centrifugo/commit/46d40e4ac3a5446c9745f8b219197166ae12a6e5 https://github.com/centrifugal/centrifugo/pull/1162 https://github.com/centrifugal/centrifugo/releases/tag/v6.8.4 https://github.com/centrifugal/centrifugo/security/advisories/GHSA-q6mr-3g59-5m8x

Frequently Asked Questions

What is CVE-2026-62963? +

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.

How do I check if I'm vulnerable to CVE-2026-62963? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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