high
CVE-2021-33503
urllib3 catastrophic backtracking in the URL authority parser on a URL containing many @ characters
- Severity
- high
- Affected product
- urllib3
- Affected versions
- urllib3 ≥ 1.25.4, < 1.26.5
- Fixed in
- urllib3 1.26.5
- Detection basis
- Component version range
- Shipped rule
- urllib3: urllib3 catastrophic backtracking in the URL authority parser on a URL containing many @ characters
- Added to NewScan
- 2026-09-30
- Detected by
- NewScan — free, self-hosted
How NewScan reports it
COMPONENT VERSION RANGE
NewScan fingerprints urllib3 from its response and reports this CVE when the detected version falls inside the affected range below.
References
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