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CVE-2021-33503

CVE

Threat entity extracted from intelligence sources

Frequency
1
occurrences
First Seen
February 18, 2026
Last Seen
February 18, 2026
API
Exploited in Wild
—
Ransomware Use
—
Public Exploits
—
Attack Vector
—

Vulnerability Overview

Exploitation Activity

Exploitation Intelligence

Multiple CVEs Address URL Handling Vulnerabilities in Python Libraries44.6

CVE-2021-33503 affects urllib3 versions before 1.26.5, causing denial of service through catastrophic backtracking when processing URLs with excessive '@' characters. CVE-2023-26159 targets follow-redirects versions before 1.15.4, which improperly handle URLs, allowing attackers to redirect traffic...

Public Exploits

Checking GitHub for proof-of-concept code…

CVE Details

Related Entities

Denial of Service