Exploit for CVE-2021-33503

An issue was discovered in urllib3 before 1.26.5. When provided with a URL containing many @ characters in the authority component, the authority regular expression exhibits catastrophic backtracking, causing a denial of service if a URL were passed as a parameter or redirected to via an HTTP redirect.

Published: 2021-06-29

CVSS: 7.5

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Download Exploit for CVE-2021-33503 here:

Use Tor Browser to access .onion links.

Check our team here:

https://wednesfieldacademy.com/exploit-411-cve-2025-8714/

https://wednesfieldacademy.com/exploit-350-cve-2025-11669/

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