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CVE-2026-48818

CVE-2026-48818 · Starlette: SSRF and NTLM credential theft via UNC paths in StaticFiles on Windows

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

Starlette is a lightweight ASGI framework/toolkit. In versions 1.0.1 and earlier, StaticFiles on Windows is vulnerable to SSRF. An UNC path such as \\attacker.com\share can cause os.path.realpath to initiate an outbound SMB connection before the path is rejected, exposing the service account’s NTLMv2 credentials for offline cracking or relay even though the HTTP response is only a 404. The issue affects default follow_symlink=False deployments, including frameworks built on Starlette such as FastAPI; POSIX systems and follow_symlink=True are unaffected. The issue is fixed in 1.1.0.

CVSS 7.5 · High · EPSS 0.4% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • starlette

    Versions
    • < 1.1.0: Affected

    No fix published

  • 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
    • 0.47.2
    • 0.47.3
    • 0.48.0
    • 0.49.0
    • 0.49.1
    • 0.49.2
    • 0.49.3
    • 0.5.0
    • 0.5.1
    • 0.5.2
    • 0.5.3
    • 0.5.4
    • 0.5.5
    • 0.50.0
    • 0.51.0
    • 0.52.0
    • 0.52.1
    • 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
    • 1.0.0
    • 1.0.0rc1
    • 1.0.1
    Affected ranges
    • ECOSYSTEM: < 1.1.0

    Update to 1.1.0

  • 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

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