How severe is CVE-2021-24163?

CVE-2021-24163 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2021-24163 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24163?

CVE-2021-24163 affects Ninjaforms Ninja Forms. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24163?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2021-24163 published?

CVE-2021-24163 was published on 2021-04-05 and last updated on 2026-06-17.

CVE-2021-24163

CVE-2021-24163 is a high-severity vulnerability in Ninjaforms Ninja Forms with a CVSS 3.x base score of 8.8. 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-862.

Key facts

Severity: High (CVSS 3.x base score 8.8)
CVSS v2: 6.5
EPSS exploit prediction: 1% (70th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-862
Affected product: Ninjaforms Ninja Forms
Published: 2021-04-05
Last modified: 2026-06-17

Description

The AJAX action, wp_ajax_ninja_forms_sendwp_remote_install_handler, did not have a capability check on it, nor did it have any nonce protection, therefore making it possible for low-level users, such as subscribers, to install and activate the SendWP Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress WordPress plugin before 3.4.34 and retrieve the client_secret key needed to establish the SendWP connection while also installing the SendWP plugin.

Frequently asked questions

What is CVE-2021-24163?: The AJAX action, wp_ajax_ninja_forms_sendwp_remote_install_handler, did not have a capability check on it, nor did it have any nonce protection, therefore making it possible for low-level users, such as subscribers, to install and activate the SendWP Ninja Forms Contact Form – The Drag and Drop Form Builder for WordPress WordPress plugin before 3.4.34 and retrieve the client_secret key needed to establish the SendWP connection while also installing the SendWP plugin.
How severe is CVE-2021-24163?: CVE-2021-24163 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2021-24163 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (70th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24163?: CVE-2021-24163 affects Ninjaforms Ninja Forms. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24163?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2021-24163 published?: CVE-2021-24163 was published on 2021-04-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:ninjaforms:ninja_forms:*:*:*:*:*:wordpress:*:*

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