CVE-2021-33880 Affecting python-websockets package, versions <9.1-1


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
2.27% (81st percentile)

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  • Snyk IDSNYK-DEBIAN14-PYTHONWEBSOCKETS-11765512
  • published10 Aug 2025
  • disclosed6 Jun 2021

Introduced: 6 Jun 2021

CVE-2021-33880  (opens in a new tab)

How to fix?

Upgrade Debian:14 python-websockets to version 9.1-1 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream python-websockets package and not the python-websockets package as distributed by Debian. See How to fix? for Debian:14 relevant fixed versions and status.

The aaugustin websockets library before 9.1 for Python has an Observable Timing Discrepancy on servers when HTTP Basic Authentication is enabled with basic_auth_protocol_factory(credentials=...). An attacker may be able to guess a password via a timing attack.

CVSS Base Scores

version 3.1