CVE-2020-7694

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).

CVSS v3 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:N/I:P/A:N

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact NONE

Integrity Impact PARTIAL

Availability Impact NONE

References

Link	Resource
https://github.com/encode/uvicorn	Product Third Party Advisory
https://snyk.io/vuln/SNYK-PYTHON-UVICORN-575560	Exploit Third Party Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:encode:uvicorn:-:*:*:*:*:*:*:*

History

No history.

Information

Published : 2020-07-27 12:15

Updated : 2023-12-10 13:27

NVD link : CVE-2020-7694

Mitre link : CVE-2020-7694

CVE.ORG link : CVE-2020-7694

JSON object : View

Products Affected

encode

uvicorn

CWE

CWE-116

Improper Encoding or Escaping of Output

CWE-94

Improper Control of Generation of Code ('Code Injection')

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