p PatchFirst

CVE-2025-54121

CVE-2025-54121 · Starlette has possible denial-of-service vector when parsing large files in multipart forms

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

Starlette is a lightweight ASGI (Asynchronous Server Gateway Interface) framework/toolkit, designed for building async web services in Python. In versions 0.47.1 and below, when parsing a multi-part form with large files (greater than the default max spool size) starlette will block the main thread to roll the file over to disk. This blocks the event thread which means the application can't accept new connections. The UploadFile code has a minor bug where instead of just checking for self._in_memory, the logic should also check if the additional bytes will cause a rollover. The vulnerability is fixed in version 0.47.2.

CVSS 5.3 · Medium · EPSS 0.7% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • starlette

    Versions
    • < 0.47.2: Affected

    No fix published

  • starlette Debian:12

    Versions
    • 0.26.1-1
    Affected ranges
    • ECOSYSTEM: < 0.26.1-1+deb12u1

    Update to 0.26.1-1+deb12u1

  • starlette Debian:13

    Affected ranges
    • ECOSYSTEM: < 0.46.1-3

    Update to 0.46.1-3

  • starlette Debian:14

    Affected ranges
    • ECOSYSTEM: < 0.46.1-3

    Update to 0.46.1-3

  • starlette PyPI

    Versions
    • 0.1.0
    • 0.1.1
    • 0.1.10
    • 0.1.11
    • 0.1.12
    • 0.1.13
    • 0.1.14
    • 0.1.15
    • 0.1.16
    • 0.1.17
    • 0.1.2
    • 0.1.3
    • 0.1.4
    • 0.1.5
    • 0.1.6
    • 0.1.7
    • 0.1.8
    • 0.1.9
    • 0.10.0
    • 0.10.1
    • 0.10.2
    • 0.10.3
    • 0.10.4
    • 0.10.5
    • 0.10.6
    • 0.10.7
    • 0.11.0
    • 0.11.1
    • 0.11.2
    • 0.11.3
    • 0.11.4
    • 0.12.0
    • 0.12.0b1
    • 0.12.0b2
    • 0.12.0b3
    • 0.12.1
    • 0.12.10
    • 0.12.11
    • 0.12.12
    • 0.12.13
    • 0.12.2
    • 0.12.3
    • 0.12.4
    • 0.12.5
    • 0.12.6
    • 0.12.7
    • 0.12.8
    • 0.12.9
    • 0.13.0
    • 0.13.1
    • 0.13.2
    • 0.13.3
    • 0.13.4
    • 0.13.5
    • 0.13.6
    • 0.13.7
    • 0.13.8
    • 0.14.0
    • 0.14.1
    • 0.14.2
    • 0.15.0
    • 0.16.0
    • 0.17.0
    • 0.17.1
    • 0.18.0
    • 0.19.0
    • 0.19.1
    • 0.2.0
    • 0.2.1
    • 0.2.2
    • 0.2.3
    • 0.20.0
    • 0.20.1
    • 0.20.2
    • 0.20.3
    • 0.20.4
    • 0.21.0
    • 0.22.0
    • 0.23.0
    • 0.23.1
    • 0.24.0
    • 0.25.0
    • 0.26.0
    • 0.26.0.post1
    • 0.26.1
    • 0.27.0
    • 0.28.0
    • 0.29.0
    • 0.3.0
    • 0.3.1
    • 0.3.2
    • 0.3.3
    • 0.3.4
    • 0.3.5
    • 0.3.6
    • 0.3.7
    • 0.30.0
    • 0.31.0
    • 0.31.1
    • 0.32.0
    • 0.32.0.post1
    • 0.33.0
    • 0.34.0
    • 0.35.0
    • 0.35.1
    • 0.36.0
    • 0.36.1
    • 0.36.2
    • 0.36.3
    • 0.37.0
    • 0.37.1
    • 0.37.2
    • 0.38.0
    • 0.38.1
    • 0.38.2
    • 0.38.3
    • 0.38.4
    • 0.38.5
    • 0.38.6
    • 0.39.0
    • 0.39.1
    • 0.39.2
    • 0.4.0
    • 0.4.1
    • 0.4.2
    • 0.40.0
    • 0.41.0
    • 0.41.1
    • 0.41.2
    • 0.41.3
    • 0.42.0
    • 0.43.0
    • 0.44.0
    • 0.45.0
    • 0.45.1
    • 0.45.2
    • 0.45.3
    • 0.46.0
    • 0.46.1
    • 0.46.2
    • 0.47.0
    • 0.47.1
    • 0.5.0
    • 0.5.1
    • 0.5.2
    • 0.5.3
    • 0.5.4
    • 0.5.5
    • 0.6.0
    • 0.6.1
    • 0.6.2
    • 0.6.3
    • 0.7.0
    • 0.7.1
    • 0.7.2
    • 0.7.3
    • 0.7.4
    • 0.8.0
    • 0.8.1
    • 0.8.2
    • 0.8.3
    • 0.8.4
    • 0.8.5
    • 0.8.6
    • 0.8.7
    • 0.8.8
    • 0.9.0
    • 0.9.1
    • 0.9.10
    • 0.9.11
    • 0.9.2
    • 0.9.3
    • 0.9.4
    • 0.9.5
    • 0.9.6
    • 0.9.7
    • 0.9.8
    • 0.9.9
    Affected ranges
    • ECOSYSTEM: < 0.47.2

    Update to 0.47.2

  • starlette Ubuntu:22.04:LTS

    Versions
    • 0.14.1-1
    • 0.16.0-1
    • 0.18.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • starlette Ubuntu:24.04:LTS

    Versions
    • 0.30.0-1
    • 0.31.1-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • starlette Ubuntu:25.10

    Versions
    • 0.46.1-2
    • 0.46.1-3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • starlette Ubuntu:26.10

    Versions
    • 0.50.0-1
    • 1.1.0-1
    • 1.3.1-1
    • 1.7.0-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • starlette Ubuntu:26.04:LTS

    Versions
    • 0.46.1-3
    • 0.50.0-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

Check your server →