Log injection in uvicorn
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-94.
Summary
This affects all versions of package uvicorn. The request logger provided by the package 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).
Why it matters now
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | uvicorn | all versions | — | No fix listed | CNA |
| — | uvicorn (PyPI) | before 0.11.7 | 0.11.7 | Patch available | GHSA-33c7-2mpw-hg34 |
- uvicorn Vendor— Affected all versions Fixed in — No fix listed CNA
- uvicorn (PyPI) Vendor— Affected before 0.11.7 Fixed in 0.11.7 Patch available GHSA-33c7-2mpw-hg34
Remediation
- Fix · GHSA-33c7-2mpw-hg34 uvicorn (PyPI) Fixed in 0.11.7 Advisory →
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
uvicorn unspecified
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2020-06215 HTTP response splitting in uvicornPriority LOW 27
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2020-7694
- 2026-10-03 Alias added: GHSA-33c7-2mpw-hg34
References
More encode Uvicorn vulnerabilities
- TI-2020-06215 HTTP response splitting in uvicorn CVSS 3.1MEDIUM 5.3
Sources
- CVE-2020-7694 · CVE Program
- CVE-2020-7694 · NVD
- FIRST EPSS
- GHSA-33c7-2mpw-hg34 · GitHub Advisory Database · CC BY 4.0
- CVE-2020-7694 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences