CVE-2021-4425 json
Defender Security <= 2.4.6 - Cross-Site Request Forgery Bypass
published 2023-07-12 3 y ago modified 2026-06-17 4 mo ago also EUVD-2021-34252
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 47%
- public exploits
- 0
- none known
Summary
The Defender Security plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 2.4.6. This is due to missing or incorrect nonce validation on the verify_otp_login_time() function. This makes it possible for unauthenticated attackers to verify a one time login via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
Patch / fix
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
0.56% chance of exploitation in the next 30 days, higher than 47% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- wordfence.com https://www.wordfence.com/threat-intel/vulnerabilities/id/e772fbbe-33d5-46fa-a041-ab07d3f9318f?source=cve referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/25-wordpress-plugins-vulnerable-to-csrf-attacks/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/ referenced PoC, tagged "exploit" by a source, unverified
- blog.nintechnet.com https://blog.nintechnet.com/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/ referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N |
Affected products
- wpmudev Defender Security – Malware Scanner, Login Security & Firewall
Classification
- Weakness
-
- CWE-352 Cross-Site Request Forgery
- Technology feeds
References
-
wordfence.com
/threat-intel/vulnerabilities/id/e772fbbe-33d5-46fa-a041-ab07d3f9318f?source=cve
exploit, patch, third-party-advisory
-
plugins.trac.wordpress.org
/changeset?sfp_email=&sfph_mail=&reponame=&old=2473684%40defender-security&new=2473684%40defender-security&sfp
patch, product
-
blog.nintechnet.com
/25-wordpress-plugins-vulnerable-to-csrf-attacks/
exploit, third-party-advisory
-
blog.nintechnet.com
/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/
exploit, third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/
exploit, third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/
exploit, third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/
exploit, third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/
exploit, third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/
exploit, third-party-advisory
Sources
- CVE List CVE-2021-4425
- NVD CVE-2021-4425
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.