6.1

CVE-2021-21337: URL Redirection to Untrusted Site ('Open Redirect') in Products.PluggableAuthService

Modified
AliasesGHSA-p44j-xrqg-4xrrPYSEC-2021-45
Published 08-03-2021Last modified 03-08-2024

Vulnerability summary

CVE-2021-21337 is a medium (CVSS 6.1) URL Redirection to Untrusted Site vulnerability in zope products.pluggableauthservice. EPSS estimates a 8.44% chance of exploitation in the next 30 days, higher than 95% of scored vulnerabilities. 2 public exploits are recorded.

Priority
Routine

Not severe (CVSS 5.7, network access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
6.1/10
010
Medium · v3.1 (NVD)
EPSS score
8.44%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits2reference, exploit-database

Timeline

  1. 08-03-2021
    PublishedVulnerability first disclosed.
  2. 03-08-2024
    Last modifiedVulnerability information updated.

Description

Products.PluggableAuthService is a pluggable Zope authentication and authorization framework. In Products.PluggableAuthService before version 2.6.0 there is an open redirect vulnerability. A maliciously crafted link to the login form and login functionality could redirect the browser to a different website. The problem has been fixed in version 2.6.1. Depending on how you have installed Products.PluggableAuthService, you should change the buildout version pin to `2.6.1` and re-run the buildout, or if you used `pip` simply do `pip install "Products.PluggableAuthService>=2.6.1".

CVSS metrics

5 scores · 3 sources · 3 versions

EPSS trend

Probability

8.44%

Chance of exploitation in the next 30 days

Percentile

95%

Versus all other CVEs

30-day change

No change 0.00 pp

From 8.44% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs
CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

2 found
  • referenceUnverified

    Exploit Reference (packetstormsecurity.com)

    Maturity: unknown

  • exploit-databasepythonUnverified

    Products.PluggableAuthService 2.6.0 - Open Redirect

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Version check

Known conditions: network-reachable, low-privilege account, user interaction (CVSS vector). Other conditions: not stated in public data.

PyPI1 product
  • products-pluggableauthservice< 7eead067898852ebd3e0f143bc51295928528dfa | < 2.6.1
Zope1 product
Zopefoundation1 product

3 vendors · 3 products

References

8 links