How severe is CVE-2021-4074?

CVE-2021-4074 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-4074 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-4074?

CVE-2021-4074 affects I-plugins Whmcs Bridge. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-4074?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-4074 published?

CVE-2021-4074 was published on 2022-01-18 and last updated on 2026-06-17.

CVE-2021-4074

CVE-2021-4074 is a medium-severity vulnerability in I-plugins Whmcs Bridge with a CVSS 3.x base score of 6.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Severity: Medium (CVSS 3.x base score 6.4)
CVSS v2: 3.5
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: I-plugins Whmcs Bridge
Published: 2022-01-18
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2021-4074?: 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.
How severe is CVE-2021-4074?: CVE-2021-4074 has a CVSS 3.x base score of 6.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-4074 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-4074?: CVE-2021-4074 affects I-plugins Whmcs Bridge. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-4074?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-4074 published?: CVE-2021-4074 was published on 2022-01-18 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:i-plugins:whmcs_bridge:*:*:*:*:*:wordpress:*:*

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