How severe is CVE-2021-39202?

CVE-2021-39202 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2021-39202 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-39202?

CVE-2021-39202 primarily affects Wordpress. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-39202?

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-2021-39202 published?

CVE-2021-39202 was published on 2021-09-09 and last updated on 2026-06-17.

CVE-2021-39202

CVE-2021-39202 is a high-severity vulnerability in Wordpress with a CVSS 3.x base score of 7.6. 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: High (CVSS 3.x base score 7.6)
CVSS v2: 3.5
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Wordpress
Published: 2021-09-09
Last modified: 2026-06-17

Description

WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. In affected versions the widgets editor introduced in WordPress 5.8 beta 1 has improper handling of HTML input in the Custom HTML feature. This leads to stored XSS in the custom HTML widget. This has been patched in WordPress 5.8. It was only present during the testing/beta phase of WordPress 5.8.

Frequently asked questions

What is CVE-2021-39202?: WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. In affected versions the widgets editor introduced in WordPress 5.8 beta 1 has improper handling of HTML input in the Custom HTML feature. This leads to stored XSS in the custom HTML widget. This has been patched in WordPress 5.8. It was only present during the testing/beta phase of WordPress 5.8.
How severe is CVE-2021-39202?: CVE-2021-39202 has a CVSS 3.x base score of 7.6, rated high severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2021-39202 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-39202?: CVE-2021-39202 primarily affects Wordpress. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-39202?: 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-2021-39202 published?: CVE-2021-39202 was published on 2021-09-09 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:wordpress:wordpress:5.8:beta1:*:*:*:*:*:*
cpe:2.3:a:wordpress:wordpress:5.8:beta2:*:*:*:*:*:*

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