PoC Index

CVE-2021-33503

HIGH 8.7EPSS 3.3%

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.

CVSS v4.0
8.7 HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
CVSS v3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v3.1
7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v2.0
5.0 MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P
EPSS
3.27% chance of exploitation in the next 30 days, 88th percentile
Published
2021-06-29
Updated
2024-08-03

Proof-of-concept exploits (1)

References

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