CVE-2020-7212
on pypi
on github
Published
Severity
CVSS v3:
7.5 HIGH
CVSS v2:
7.8 HIGH
Description
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
Configurations
CPE23 | Version Start | Version End | Exact Version |
---|---|---|---|
cpe:2.3:a:python:urllib3:*:*:*:*:*:*:*:* | 1.25.2 (including) | 1.25.7 (including) | * |