TI-2021-16587 Aliases CVE-2021-39202

WordPress 5.8 beta: Stored Cross-Site Scripting (XSS) vulnerability in widget

LOW 35CWE-79Published 2021-09-09 · Updated 2024-08-04

Key facts

Attack vector: Network
Privileges required: Low
User interaction: Required
Attack complexity: Low
Impact type: Cross-site scripting
Confidentiality · integrity · availability: High · Low · None
Fix status: No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-79.

Summary

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.

Why it matters now

EPSS 0.0082 57th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
WordPress	wordpress-develop	5.8 beta 1; 5.8 beta 2	—	No fix listed	CNA

wordpress-develop VendorWordPress Affected 5.8 beta 1; 5.8 beta 2 Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:a:wordpress:wordpress:5.8:beta1::::::	5.8 beta1	Vulnerable	WordPress
cpe:2.3:a:wordpress:wordpress:5.8:beta2::::::	5.8 beta2	Vulnerable	WordPress

cpe:2.3:a:wordpress:wordpress:5.8:beta1:*:*:*:*:*:* Versions 5.8 beta1 Vulnerable ·WordPress
cpe:2.3:a:wordpress:wordpress:5.8:beta2:*:*:*:*:*:* Versions 5.8 beta2 Vulnerable ·WordPress

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-39202

References

Advisory 1

https://github.com/WordPress/wordpress-develop/security/advisories/GHSA-fr6h-3855-j297

Other 1

https://hackerone.com/reports/1222797

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TI-2026-83466 Predictable staging paths let attackers run code in WordPress Core KEVCVSS 3.1HIGH 8.1
TI-2026-59973 An unauthenticated attacker can make `get_page_template()` page-template resolution… KEVCVSS 3.1HIGH 8.1
TI-2016-08129 The isMail transport in PHPMailer before 5.2.20 might allow remote attackers to pass… CVSS 3.1CRITICAL 9.8
TI-2026-42844 WordPress < 7.0.2 - Facilitated SQL Injection via author__not_in in WP_Query KEVCVSS 3.1MEDIUM 5.9

See all 356 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences