CVE-2021-4074

WHMCS Bridge <= 6.1 Subscriber+ Stored Cross-Site Scripting

Description

The WHMCS Bridge WordPress plugin is vulnerable to Stored Cross-Site Scripting via the cc_whmcs_bridge_url parameter found in the ~/whmcs-bridge/bridge_cp.php file which allows attackers to inject arbitrary web scripts, in versions up to and including 6.1. Due to missing authorization checks on the cc_whmcs_bridge_add_admin function, low-level authenticated users such as subscribers can exploit this vulnerability.

Remediation

Solution:

  • Update to version 6.3, or newer.

Category

6.4
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.12%
Third-Party Advisory wordpress.org Third-Party Advisory wordfence.com
Affected: WHMCS Bridge WHMCS Bridge
Published at:
Updated at:

References

Link Tags
https://www.wordfence.com/vulnerability-advisories/#CVE-2021-4074 third party advisory
https://plugins.trac.wordpress.org/changeset?sfp_email=&sfph_mail=&reponame=&old=2653041%40whmcs-bridge&new=2653041%40whmcs-bridge&sfp_email=&sfph_mail= issue tracking third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-4074?
CVE-2021-4074 has been scored as a medium severity vulnerability.
How to fix CVE-2021-4074?
To fix CVE-2021-4074: Update to version 6.3, or newer.
Is CVE-2021-4074 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-4074 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-4074?
CVE-2021-4074 affects WHMCS Bridge WHMCS Bridge.
This platform uses data from the NIST NVD, MITRE CVE, MITRE CWE, First.org and CISA KEV but is not endorsed or certified by these entities. CVE is a registred trademark of the MITRE Corporation and the authoritative source of CVE content is MITRE's CVE web site. CWE is a registred trademark of the MITRE Corporation and the authoritative source of CWE content is MITRE's CWE web site.
© 2025 Under My Watch. All Rights Reserved.