CVE-2026-103424 (GCVE-0-2026-103424)

Vulnerability from cvelistv5 – Published: 2026-10-10 04:26 – Updated: 2026-10-11 12:23
VLAI
Title
Anti-Spam by CleanTalk <= 6.88 - Unauthenticated Stored Cross-Site Scripting via Comment Content via ContactsEncoder Greedy Regex
Summary
The Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'comment' parameter in all versions up to, and including, 6.88 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This vulnerability is exploitable once a comment from the attacker's email address has been approved; on default WordPress installations, only the first comment from a given email address is held for moderation, meaning subsequent comments auto-approve and immediately expose the payload to site visitors.
Severity
5.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-11 12:17 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2203 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
cleantalk Anti-Spam by CleanTalk – Spam Protection Without CAPTCHA Affected: 0 , ≤ 6.88 (semver)
guessed Create a notification for this product.
Credits
Maciej Komorowski
Show details on NVD website
To clipboard 

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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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