CVE-2021-39349

Name: CVE-2021-39349
Creator: NVD / NIST
Published: 2021-10-15T13:15:08.07+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 4.8/10EPSS 1.10%

Last modified Jun 17, 2026

CVE-2021-39349 is a medium-severity vulnerability rated 4.8/10 on the CVSS scale. The Author Bio Box WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via several parameters found in the ~/includes/admin/class-author-bio-box-admin.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.3.1. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.. EPSS estimates a 1.10% chance of exploitation in the next 30 days.

Description

The Author Bio Box WordPress plugin is vulnerable to Stored Cross-Site Scripting due to insufficient input validation and sanitization via several parameters found in the ~/includes/admin/class-author-bio-box-admin.php file which allowed attackers with administrative user access to inject arbitrary web scripts, in versions up to and including 3.3.1. This affects multi-site installations where unfiltered_html is disabled for administrators, and sites where unfiltered_html is disabled.

Metrics

CVSS 3.1

4.8/10

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

EPSS Probability

1.10%

61.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Author Bio Box Project	Author Bio Box	<= 3.3.1

References

https://github.com/BigTiger2020/word-press/blob/main/Author%20Bio%20Box.mdExploit, Third Party Advisory
https://plugins.trac.wordpress.org/changeset/2613798/author-bio-box/tags/3.3.2/includes/admin/class-author-bio-box-admin.phpPatch, Third Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39349Third Party Advisory
https://github.com/BigTiger2020/word-press/blob/main/Author%20Bio%20Box.mdExploit, Third Party Advisory
https://plugins.trac.wordpress.org/changeset/2613798/author-bio-box/tags/3.3.2/includes/admin/class-author-bio-box-admin.phpPatch, Third Party Advisory
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39349Third Party Advisory

Timeline

Published: Oct 15, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-39349?

How severe is CVE-2021-39349?

CVE-2021-39349 has a CVSS score of 4.8/10 (MEDIUM severity). The EPSS model estimates a 1.10% probability of exploitation in the next 30 days.

How do I fix CVE-2021-39349?

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-2021-39349?

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

Scan your code now

Source: NVD / NIST