PyPI: uvicorn
CVE-2020-7694
Safety vulnerability ID: SFTY-20200727-49565
Safety legacy ID: pyup.io-38664
The request logger provided by Uvicorn prior to version 0.11.7 is vulnerable to ASNI escape sequence injection. Whenever any HTTP request is received, the default behaviour of uvicorn is to log its details to either the console or a log file. When attackers request crafted URLs with percent-encoded escape sequences, the logging component will log the URL after it's been processed with urllib.parse.unquote, therefore converting any percent-encoded characters into their single-character equivalent, which can have special meaning in terminal emulators. By requesting URLs with crafted paths, attackers can: * Pollute uvicorn's access logs, therefore jeopardising the integrity of such files. * Use ANSI sequence codes to attempt to interact with the terminal emulator that's displaying the logs (either in real time or from a file). See: CVE-2020-7694.
Overview
Log injection in uvicorn
Advisory
The request logger provided by Uvicorn prior to version 0.11.7 is vulnerable to ASNI escape sequence injection. Whenever any HTTP request is received, the default behaviour of uvicorn is to log its details to either the console or a log file. When attackers request crafted URLs with percent-encoded escape sequences, the logging component will log the URL after it's been processed with urllib.parse.unquote, therefore converting any percent-encoded characters into their single-character equivalent, which can have special meaning in terminal emulators. By requesting URLs with crafted paths, attackers can: * Pollute uvicorn's access logs, therefore jeopardising the integrity of such files. * Use ANSI sequence codes to attempt to interact with the terminal emulator that's displaying the logs (either in real time or from a file). See: CVE-2020-7694.
How to Fix
Mitigation and Workarounds
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Vulnerable Functions
Functions linked to known vulnerabilities.
References
- https://getsafety.com/vulnerabilities/SFTY-20200727-49565/CVE-2020-7694
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-7694
- https://github.com/encode/uvicorn
- https://snyk.io/vuln/SNYK-PYTHON-UVICORN-575560
- https://nvd.nist.gov/vuln/detail/CVE-2020-7694
- https://snyk.io/vuln/SNYK-PYTHON-UVICORN-575560
- https://github.com/encode/uvicorn/issues/723
- https://github.com/encode/uvicorn/commit/895807f94ea9a8e588605c12076b7d7517cda503
- https://github.com/pypa/advisory-database/tree/main/vulns/uvicorn/PYSEC-2020-150.yaml
- https://github.com/advisories/GHSA-33c7-2mpw-hg34
Verified by Safety
Our Cybersecurity Intelligence Team reviewed this vulnerability. We combine public data with our own research to find issues not yet reported to public sources.
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