CVE-2026-62963 (GCVE-0-2026-62963)
Vulnerability from cvelistv5 – Published: 2026-07-16 19:34 – Updated: 2026-07-17 13:46
VLAI
EPSS
VEX
Title
Centrifugo: Decompression bomb DoS via permessage-deflate in unidirectional WebSocket transport
Summary
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.
Severity
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-17 13:46 UTC
CWE
- CWE-409 - Improper Handling of Highly Compressed Data (Data Amplification)
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/centrifugal/centrifugo/securit… | x_refsource_CONFIRM |
| https://github.com/centrifugal/centrifugo/pull/1162 | x_refsource_MISC |
| https://github.com/centrifugal/centrifugo/commit/… | x_refsource_MISC |
| https://github.com/centrifugal/centrifugo/release… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| centrifugal | centrifugo |
Affected:
< 6.8.4
|
guessed |
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The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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