CVE-2021-34637

Name: CVE-2021-34637
Creator: NVD / NIST
Published: 2021-08-02T21:15:08.66+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 0.70%

Last modified Jun 17, 2026

CVE-2021-34637 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. The Post Index WordPress plugin is vulnerable to Cross-Site Request Forgery via the OptionsPage function found in the ~/php/settings.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 0.7.5.. EPSS estimates a 0.70% chance of exploitation in the next 30 days.

Description

The Post Index WordPress plugin is vulnerable to Cross-Site Request Forgery via the OptionsPage function found in the ~/php/settings.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 0.7.5.

Metrics

CVSS 3.1

8.8/10

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

EPSS Probability

0.70%

48.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Post Index Project	Post Index	<= 0.7.5

References

https://plugins.trac.wordpress.org/browser/post-index/trunk/php/settings.php#L86Exploit, Third Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34637Third Party Advisory
https://plugins.trac.wordpress.org/browser/post-index/trunk/php/settings.php#L86Exploit, Third Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-34637Third Party Advisory

Timeline

Published: Aug 2, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-34637?

How severe is CVE-2021-34637?

CVE-2021-34637 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 0.70% probability of exploitation in the next 30 days.

How do I fix CVE-2021-34637?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-34637?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST