The _encode_invalid_chars function in util/url.py in the urllib3 library 1.25.2 through 1.25.7 for Python allows a denial of service (CPU consumption) because of an inefficient algorithm. The percent_encodings array contains all matches of percent encodings. It is not deduplicated. For a URL of length N, the size of percent_encodings may be up to O(N). The next step (normalize existing percent-encoded bytes) also takes up to O(N) for each step, so the total time is O(N^2). If percent_encodings were deduplicated, the time to compute _encode_invalid_chars would be O(kN), where k is at most 484 ((10+6*2)^2).
References
| Link | Resource |
|---|---|
| https://github.com/urllib3/urllib3/blob/master/CHANGES.rst | Release Notes Third Party Advisory |
| https://github.com/urllib3/urllib3/commit/a74c9cfbaed9f811e7563cfc3dce894928e0221a | Patch Third Party Advisory |
| https://pypi.org/project/urllib3/1.25.8/ | Release Notes Vendor Advisory |
| https://github.com/urllib3/urllib3/blob/master/CHANGES.rst | Release Notes Third Party Advisory |
| https://github.com/urllib3/urllib3/commit/a74c9cfbaed9f811e7563cfc3dce894928e0221a | Patch Third Party Advisory |
| https://pypi.org/project/urllib3/1.25.8/ | Release Notes Vendor Advisory |
Configurations
History
21 Nov 2024, 05:36
| Type | Values Removed | Values Added |
|---|---|---|
| References | () https://github.com/urllib3/urllib3/blob/master/CHANGES.rst - Release Notes, Third Party Advisory | |
| References | () https://github.com/urllib3/urllib3/commit/a74c9cfbaed9f811e7563cfc3dce894928e0221a - Patch, Third Party Advisory | |
| References | () https://pypi.org/project/urllib3/1.25.8/ - Release Notes, Vendor Advisory |
Information
Published : 2020-03-06 20:15
Updated : 2024-11-21 05:36
NVD link : CVE-2020-7212
Mitre link : CVE-2020-7212
CVE.ORG link : CVE-2020-7212
JSON object : View
Products Affected
python
- urllib3
CWE
CWE-400
Uncontrolled Resource Consumption