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CVE-2026-34531

CVE-2026-34531 · Flask-HTTPAuth invokes token verification callback when missing or empty token was given by client

This page contains facts from public vulnerability sources. Check the original advisory before updating.

Flask-HTTPAuth provides Basic, Digest and Token HTTP authentication for Flask routes. Prior to version 4.8.1, in a situation where the client makes a request to a token protected resource without passing a token, or passing an empty token, Flask-HTTPAuth would invoke the application's token verification callback function with the token argument set to an empty string. If the application had any users in its database with an empty string set as their token, then it could potentially authenticate the client request against any of those users. This issue has been patched in version 4.8.1.

CVSS 6.5 · Medium · EPSS 0.3% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • flask-httpauth

    Versions
    • < 4.8.1: Affected

    No fix published

  • python-flask-httpauth Debian:12

    Versions
    • 4.5.0-4
    • 4.8.0-1
    • 4.8.1-1.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Debian:13

    Versions
    • 4.8.0-1
    • 4.8.1-1.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Debian:14

    Versions
    • 4.8.0-1
    Affected ranges
    • ECOSYSTEM: < 4.8.1-1.1

    Update to 4.8.1-1.1

  • flask-httpauth PyPI

    Versions
    • 1.0.0
    • 1.1.0
    • 2.0.0
    • 2.1.0
    • 2.2.0
    • 2.2.1
    • 2.3.0
    • 2.4.0
    • 2.5.0
    • 2.6.0
    • 2.7.0
    • 2.7.1
    • 2.7.2
    • 3.0.0
    • 3.0.1
    • 3.0.2
    • 3.1.0
    • 3.1.1
    • 3.1.2
    • 3.2.0
    • 3.2.1
    • 3.2.2
    • 3.2.3
    • 3.2.4
    • 3.3.0
    • 4.0.0
    • 4.1.0
    • 4.2.0
    • 4.3.0
    • 4.4.0
    • 4.5.0
    • 4.6.0
    • 4.7.0
    • 4.8.0
    Affected ranges
    • ECOSYSTEM: < 4.8.1

    Update to 4.8.1

  • python-flask-httpauth Ubuntu:16.04:LTS

    Versions
    • 2.2.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:18.04:LTS

    Versions
    • 3.2.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:20.04:LTS

    Versions
    • 3.2.4-3
    • 3.2.4-3.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:22.04:LTS

    Versions
    • 3.2.4-3.1
    • 4.5.0-1
    • 4.5.0-2
    • 4.5.0-3
    • 4.5.0-4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:24.04:LTS

    Versions
    • 4.5.0-4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:25.10

    Versions
    • 4.8.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:26.10

    Versions
    • 4.8.0-1
    • 4.8.1-1.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • python-flask-httpauth Ubuntu:26.04:LTS

    Versions
    • 4.8.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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