How severe is CVE-2021-36788?

CVE-2021-36788 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-36788 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-36788?

CVE-2021-36788 affects Yoast Yoast Seo. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-36788?

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

When was CVE-2021-36788 published?

CVE-2021-36788 was published on 2021-08-13 and last updated on 2026-06-17.

CVE-2021-36788

CVE-2021-36788 is a medium-severity vulnerability in Yoast Yoast Seo with a CVSS 3.x base score of 5.4. 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 5.4)
CVSS v2: 3.5
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-79
Affected product: Yoast Yoast Seo
Published: 2021-08-13
Last modified: 2026-06-17

Description

The yoast_seo (aka Yoast SEO) extension before 7.2.3 for TYPO3 allows XSS.

Frequently asked questions

What is CVE-2021-36788?: The yoast_seo (aka Yoast SEO) extension before 7.2.3 for TYPO3 allows XSS.
How severe is CVE-2021-36788?: CVE-2021-36788 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-36788 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-36788?: CVE-2021-36788 affects Yoast Yoast Seo. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-36788?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-36788 published?: CVE-2021-36788 was published on 2021-08-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:yoast:yoast_seo:*:*:*:*:*:typo3:*:*

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