CVE-2026-42544 (GCVE-0-2026-42544)

Vulnerability from cvelistv5 – Published: 2026-05-12 21:46 – Updated: 2026-05-18 15:09
VLAI
Title
Granian: Unauthenticated DoS via WebSocket subprotocol header panic
Summary
Granian is a Rust HTTP server for Python applications. From 1.2.0 to 2.7.4, Granian aborts a worker process when an unauthenticated client sends a WebSocket upgrade request whose Sec-WebSocket-Protocol header contains non-ASCII bytes. The crash happens in Granian's WebSocket scope construction path, before the ASGI application is invoked. This vulnerability is fixed in 2.7.4.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-18 15:09 UTC
CWE
  • CWE-20 - Improper Input Validation
  • CWE-248 - Uncaught Exception
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7771 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
emmett-framework granian Affected: >= 1.2.0, < 2.7.4
guessed Create a notification for this product.
Show details on NVD website
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