How severe is CVE-2021-24608?

CVE-2021-24608 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-24608 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-24608?

CVE-2021-24608 affects Strategy11 Formidable Form Builder. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-24608?

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

When was CVE-2021-24608 published?

CVE-2021-24608 was published on 2021-10-25 and last updated on 2026-06-17.

CVE-2021-24608

CVE-2021-24608 is a medium-severity vulnerability in Strategy11 Formidable Form Builder with a CVSS 3.x base score of 4.8. 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-79.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
CVSS v2: 3.5
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Strategy11 Formidable Form Builder
Published: 2021-10-25
Last modified: 2026-06-17

Description

The Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress plugin before 5.0.07 does not sanitise and escape its Form's Labels, allowing high privileged users to perform Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed

Frequently asked questions

What is CVE-2021-24608?: The Formidable Form Builder – Contact Form, Survey & Quiz Forms Plugin for WordPress plugin before 5.0.07 does not sanitise and escape its Form's Labels, allowing high privileged users to perform Cross-Site Scripting attacks even when the unfiltered_html capability is disallowed
How severe is CVE-2021-24608?: CVE-2021-24608 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-24608 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-24608?: CVE-2021-24608 affects Strategy11 Formidable Form Builder. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-24608?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-24608 published?: CVE-2021-24608 was published on 2021-10-25 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:strategy11:formidable_form_builder:*:*:*:*:*:wordpress:*:*

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