CVE-2021-4407 json
Custom Banners <= 3.2.2 - Cross-Site Request Forgery Bypass
published 3y ago modified 4mo ago also EUVD-2021-34234
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 32%
- public exploits
- 0
- none known
Summary
The Custom Banners plugin for WordPress is vulnerable to Cross-Site Request Forgery in versions up to, and including, 3.2.2 This is due to missing or incorrect nonce validation on the saveCustomFields() function. This makes it possible for unauthenticated attackers to save custom fields via a forged request granted they can trick a site administrator into performing an action such as clicking on a link.
Patch / fix
Is CVE-2021-4407 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2y ago
Exploit prediction
0.38% chance of exploitation in the next 30 days, higher than 32% of all scored CVEs (FIRST EPSS, 2026-11-09).
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
- ghuger Custom Banners
Classification
- Weakness
-
- CWE-352 Cross-Site Request Forgery
- Technology feeds
References
-
plugins.trac.wordpress.org
/changeset?sfp_email=&sfph_mail=&reponame=&old=2473385%40custom-banners&new=2473385%40custom-banners&sfp_email
patch
-
wordfence.com
/threat-intel/vulnerabilities/id/8f4c086d-8209-4212-9d91-67238c1a9143?source=cve
third-party-advisory
-
blog.nintechnet.com
/25-wordpress-plugins-vulnerable-to-csrf-attacks/
third-party-advisory
-
blog.nintechnet.com
/more-wordpress-plugins-and-themes-vulnerable-to-csrf-attacks/
not-applicable
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-3/
not-applicable
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-2/
not-applicable
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-1/
third-party-advisory
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-5/
not-applicable
-
blog.nintechnet.com
/multiple-wordpress-plugins-fixed-csrf-vulnerabilities-part-4/
not-applicable
Sources
- CVE List CVE-2021-4407
- NVD CVE-2021-4407
Fencer Intel 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.