CVE-2021-4404
Event Espresso 4 Decaf <= 4.10.11 - Cross-Site Request Forgery Bypass
- Published
- Updated
- Reserved
- Assigned by
- Wordfence
Description
The Event Espresso 4 Decaf plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 4.10.11. This is due to missing or incorrect nonce validation on the ajaxHandler() function. This makes it possible for unauthenticated attackers to op into notifications via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
Timeline
ID reserved
By Wordfence
- 1 day later
· 1 day later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| WordfenceCNA (assigner) | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
| NVDNVD · Modified | 3.1 | Medium4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
- EPSS (exploitation in 30 days)
- 0.39% · top 67% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: no · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 4.3.
Weakness
Affected products
eventespresso · Event Espresso – Event Registration & Ticketing Sales
- affected ≤ 4.10.11
References (9)
- https://www.wordfence.com/threat-intel/vulnerabilities/id/89d3a9da-2496-4f75-ad8f-65629f198fe5?source=cve (opens in a new tab)x_transferred
- https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/ (opens in a new tab)x_transferred
- https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/ (opens in a new tab)x_transferred
- https://plugins.trac.wordpress.org/changeset/2554360/event-espresso-decaf/trunk/core/domain/services/pue/Stats.php (opens in a new tab)x_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-4404)Record last updated .