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CVE-2021-39214

CVE-2021-39214 · Lacking Protection against HTTP Request Smuggling in mitmproxy

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

mitmproxy is an interactive, SSL/TLS-capable intercepting proxy. In mitmproxy 7.0.2 and below, a malicious client or server is able to perform HTTP request smuggling attacks through mitmproxy. This means that a malicious client/server could smuggle a request/response through mitmproxy as part of another request/response's HTTP message body. While a smuggled request is still captured as part of another request's body, it does not appear in the request list and does not go through the usual mitmproxy event hooks, where users may have implemented custom access control checks or input sanitization. Unless one uses mitmproxy to protect an HTTP/1 service, no action is required. The vulnerability has been fixed in mitmproxy 7.0.3 and above.

CVSS 8.1 · High · EPSS 1.1% · Fix available

Published
Updated

Stack: system · python

Affected products and versions

  • mitmproxy

    Versions
    • < 7.0.3: Affected

    No fix published

  • mitmproxy Debian:12

    Affected ranges
    • ECOSYSTEM: < 8.1.1-1

    Update to 8.1.1-1

  • mitmproxy Debian:14

    Versions
    • 0.10-1
    • 0.10-2
    • 0.10.1-1
    • 0.10.1-2
    • 0.11.3-1
    • 0.11.3-2
    • 0.11.3-3
    • 0.12.1-1
    • 0.12.1-2
    • 0.13-1
    • 0.15-1
    • 0.15-2
    • 0.18.1-1
    • 0.18.1-2
    • 0.18.2-1
    • 0.18.2-2
    • 0.18.2-3
    • 0.18.2-4
    • 0.18.2-5
    • 0.18.2-6
    • 0.6-1
    • 0.6-2
    • 0.6-3
    • 0.7-1
    • 0.8-1
    • 0.8-2
    • 0.9.1-1
    • 0.9.1-2
    • 0.9.2-1
    • 0.9.2-2
    • 2.0.2-1
    • 2.0.2-2
    • 2.0.2-3
    • 2.0.2-4
    • 3.0.3-1
    • 3.0.4-1
    • 4.0.4-1
    • 4.0.4-2
    • 4.0.4-3
    • 4.0.4-4
    • 4.0.4-5
    • 4.0.4-6
    • 4.0.4-6.1
    • 5.1.1-1
    • 5.1.1-2
    • 5.3.0-1
    • 5.3.0-2
    • 5.3.0-3
    • 6.0.2-1
    • 6.0.2-2
    Affected ranges
    • ECOSYSTEM: < 8.1.1-1

    Update to 8.1.1-1

  • mitmproxy PyPI

    Versions
    • 0.10
    • 0.10.1
    • 0.11
    • 0.11.1
    • 0.11.2
    • 0.11.3
    • 0.12.0
    • 0.12.1
    • 0.13
    • 0.14.0
    • 0.15
    • 0.16
    • 0.17
    • 0.18.1
    • 0.18.2
    • 0.18.3
    • 0.8
    • 0.8.1
    • 0.9
    • 0.9.1
    • 0.9.2
    • 1.0.0
    • 1.0.1
    • 1.0.2
    • 2.0.0
    • 2.0.1
    • 2.0.2
    • 3.0.0
    • 3.0.1
    • 3.0.2
    • 3.0.3
    • 3.0.4
    • 4.0.0
    • 4.0.1
    • 4.0.3
    • 4.0.4
    • 5.0.0
    • 5.0.1
    • 5.1.0
    • 5.1.1
    • 5.2
    • 5.3.0
    • 6.0.0
    • 6.0.1
    • 6.0.2
    • 7.0.0
    • 7.0.1
    • 7.0.2
    Affected ranges
    • ECOSYSTEM: < 7.0.3

    Update to 7.0.3

  • mitmproxy Ubuntu:16.04:LTS

    Versions
    • 0.11.3-3
    • 0.12.1-2
    • 0.13-1
    • 0.15-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:18.04:LTS

    Versions
    • 2.0.2-2
    • 2.0.2-3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:20.04:LTS

    Versions
    • 4.0.4-6
    • 4.0.4-6.1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:22.04:LTS

    Versions
    • 6.0.2-1
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:24.04:LTS

    Versions
    • 8.1.1-2
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:25.10

    Versions
    • 8.1.1-2
    • 8.1.1-3
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:26.10

    Versions
    • 8.1.1-4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

  • mitmproxy Ubuntu:26.04:LTS

    Versions
    • 8.1.1-3
    • 8.1.1-4
    Affected ranges
    • ECOSYSTEM: (−∞, +∞)

    No fix published

Original sources

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