Post metadata modification via missing nonce validation
Published Jul 1, 2023 · Updated Apr 8, 2026
Cross-site request forgery in Rucy 0.4.4 and earlier allows remote attackers to write WordPress post metadata through forged requests. The save_rc_post_meta() function accepts state-changing post metadata without a valid WordPress nonce, so a request can update a post outside the intended editor workflow. Exploitation requires a logged-in site administrator to submit the attacker-controlled request, and the demonstrated consequence is unauthorized post-metadata modification.
Summary
What happened
Cross-site request forgery in Rucy 0.4.4 and earlier allows remote attackers to write WordPress post metadata through forged requests. The save_rc_post_meta() function accepts state-changing post metadata without a valid WordPress nonce, so a request can update a post outside the intended editor workflow. Exploitation requires a logged-in site administrator to submit the attacker-controlled request, and the demonstrated consequence is unauthorized post-metadata modification.
The record
- CVE
- CVE-2021-4396
- Published
- Jul 1, 2023
- Updated
- Apr 8, 2026
- Vendor
- Rucy Project
- Product
- Rucy
- Classifications
- CWE-352, T1190
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 1, 2023CVE publishedPublication date reported by the CVE source.
- Apr 8, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <=0.4.4
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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