What is CVE-2021-31779?

CVE-2021-31779 is a medium-severity vulnerability in Yoast Seo, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.4/10. Published 2021-04-28.

How severe is CVE-2021-31779?

Medium severity. CVSS v3 base score is 6.4 out of 10.

SSRF in Yoast Seo

CVE-2021-31779

The yoast_seo (aka Yoast SEO) extension before 7.2.1 for TYPO3 allows SSRF via a backend user account.

Vulnerability class: SSRF (Server-Side Request Forgery)

Published 2021-04-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.005 (38.7th percentile), scored 2026-10-01.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 39th percentile — 38.7% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

Yoast Seo

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

typo3.org/security/advisory/typo3-ext-sa-2021-006 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2021-31779?: CVE-2021-31779 is a medium-severity vulnerability in Yoast Seo, classified under Server-Side Request Forgery (SSRF). CVSS score: 6.4/10. Published 2021-04-28.
How severe is CVE-2021-31779?: Medium severity. CVSS v3 base score is 6.4 out of 10.