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CVE-2020-8492

MEDIUM severity · CVSS 6.5 · Uncontrolled resource consumption
6.5CVSS MEDIUM

Summary

Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7 through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
Confidentiality impactNone
Integrity impactNone
Availability impactHigh
Exploit probability (EPSS)7%

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

Affected products we track (1)

Recommendation

Apply the vendor fix in your normal patch cycle. Open any affected product above for its exact safe version.

Official patch: https://github.com/python/cpython/pull/18284 ↗