Open Redirect in Python

CVE-2021-28861

Python 3.x through 3.10 has an open redirection vulnerability in lib/http/server.py due to no protection against multiple (/) at the beginning of URI path which may leads to information disclosure. NOTE: this is disputed by a third party because the http.server.html documentation page states "Warning: http.server is not recommended for production. It only implements basic security checks."

Vulnerability class: Open Redirect

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.4 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:N/A:N.

EPSS exploit prediction

EPSS: 0.025 (84.4th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 84th percentile — 84.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-28861: held from 0.025 to 0.025.

EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-28861?
CVE-2021-28861 is a high-severity vulnerability in Python, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 7.4/10. Published 2022-08-23.
How severe is CVE-2021-28861?
High severity. CVSS v3 base score is 7.4 out of 10.
Is CVE-2021-28861 known to be exploited?
2 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.