CVE-2019-16521

Name: CVE-2019-16521
Creator: NVD / NIST
Published: 2019-10-16T15:15:15.27+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 6.1/10EPSS 1.40%

Last modified Jun 17, 2026

CVE-2019-16521 is a medium-severity vulnerability rated 6.1/10 on the CVSS scale. The broken-link-checker plugin through 1.11.8 for WordPress (aka Broken Link Checker) is susceptible to Reflected XSS due to improper encoding and insertion of an HTTP GET parameter into HTML. The filter function on the page listing all detected broken links can be exploited by providing an XSS payload in the s_filter GET parameter in a filter_id=search request. EPSS estimates a 1.40% chance of exploitation in the next 30 days.

Description

The broken-link-checker plugin through 1.11.8 for WordPress (aka Broken Link Checker) is susceptible to Reflected XSS due to improper encoding and insertion of an HTTP GET parameter into HTML. The filter function on the page listing all detected broken links can be exploited by providing an XSS payload in the s_filter GET parameter in a filter_id=search request. NOTE: this is an end-of-life product.

Metrics

CVSS 3.1

6.1/10

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

EPSS Probability

1.40%

68.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-79

Affected Software

Vendor	Product	Versions
Managewp	Broken Link Checker	<= 1.11.8

References

http://www.openwall.com/lists/oss-security/2019/10/16/3Exploit, Mailing List, Third Party Advisory
https://github.com/sbaresearch/advisories/tree/public/2019/SBA-ADV-20190913-02_WordPress_Plugin_Broken_Link_CheckerExploit, Third Party Advisory
https://wordpress.org/plugins/broken-link-checker/#developersProduct, Third Party Advisory
https://wpvulndb.com/vulnerabilities/9917Third Party Advisory
http://www.openwall.com/lists/oss-security/2019/10/16/3Exploit, Mailing List, Third Party Advisory
https://github.com/sbaresearch/advisories/tree/public/2019/SBA-ADV-20190913-02_WordPress_Plugin_Broken_Link_CheckerExploit, Third Party Advisory
https://wordpress.org/plugins/broken-link-checker/#developersProduct, Third Party Advisory
https://wpvulndb.com/vulnerabilities/9917Third Party Advisory

Timeline

Published: Oct 16, 2019
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2019-16521?

How severe is CVE-2019-16521?

CVE-2019-16521 has a CVSS score of 6.1/10 (MEDIUM severity). The EPSS model estimates a 1.40% probability of exploitation in the next 30 days.

How do I fix CVE-2019-16521?

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-2019-16521?

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

Scan your code now

Source: NVD / NIST