What is CVE-2020-27666?

CVE-2020-27666 is a medium-severity vulnerability in Strapi, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2020-10-22.

How severe is CVE-2020-27666?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Is CVE-2020-27666 known to be exploited?

1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.

XSS in Strapi

CVE-2020-27666

Strapi before 3.2.5 has stored XSS in the wysiwyg editor's preview feature.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2020-10-22 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.007 (51.9th percentile), scored 2026-09-30.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 52nd percentile — 51.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.007 · newest: 0.007 · change: 0.000

Affected products

Strapi

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

Public proof-of-concept exploits

ossf-cve-benchmark/CVE-2020-27666

References

github.com/strapi/strapi/releases/tag/v3.2.5 (Third Party Advisory, Release Notes)
github.com/strapi/strapi/pull/8440 (Patch, Third Party Advisory)

Frequently asked questions

What is CVE-2020-27666?: CVE-2020-27666 is a medium-severity vulnerability in Strapi, classified under Cross-site Scripting. CVSS score: 5.4/10. Published 2020-10-22.
How severe is CVE-2020-27666?: Medium severity. CVSS v3 base score is 5.4 out of 10.
Is CVE-2020-27666 known to be exploited?: 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.