How severe is CVE-2021-36872?

CVE-2021-36872 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-36872 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36872?

CVE-2021-36872 affects Wordpress Popular Posts Project Wordpress Popular Posts. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-36872?

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

When was CVE-2021-36872 published?

CVE-2021-36872 was published on 2021-09-23 and last updated on 2026-06-17.

CVE-2021-36872

CVE-2021-36872 is a medium-severity vulnerability in Wordpress Popular Posts Project Wordpress Popular Posts with a CVSS 3.x base score of 5.5. 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 5.5)
CVSS v2: 3.5
EPSS exploit prediction: 1% (43rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Wordpress Popular Posts Project Wordpress Popular Posts
Published: 2021-09-23
Last modified: 2026-06-17

Description

Authenticated Persistent Cross-Site Scripting (XSS) vulnerability in WordPress Popular Posts plugin (versions <= 5.3.3). Vulnerable at &widget-wpp[2][post_type].

Frequently asked questions

What is CVE-2021-36872?: Authenticated Persistent Cross-Site Scripting (XSS) vulnerability in WordPress Popular Posts plugin (versions <= 5.3.3). Vulnerable at &widget-wpp[2][post_type].
How severe is CVE-2021-36872?: CVE-2021-36872 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-36872 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (43rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36872?: CVE-2021-36872 affects Wordpress Popular Posts Project Wordpress Popular Posts. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36872?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36872 published?: CVE-2021-36872 was published on 2021-09-23 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:wordpress_popular_posts_project:wordpress_popular_posts:*:*:*:*:*:wordpress:*:*

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