CVE-2026-2121 (GCVE-0-2026-2121)

Vulnerability from cvelistv5 – Published: 2026-03-21 03:27 – Updated: 2026-04-08 17:28
VLAI?
Title
Weaver Show Posts <= 1.8.1 - Authenticated (Administrator+) Stored Cross-Site Scripting via 'Additional Classes to Wrap Posts' Widget Setting
Summary
The Weaver Show Posts plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'add_class' parameter in all versions up to, and including, 1.8.1. This is due to insufficient input sanitization and output escaping on user supplied attributes. This makes it possible for authenticated attackers, with Administrator-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This primarily affects multisite installations where Administrators do not have the unfiltered_html capability.
Severity ?
4.4 (Medium)
CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:L/I:L/A:N
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version
wpweaver Weaver Show Posts Affected: 0 , ≤ 1.8.1 (semver)
Create a notification for this product.
Credits
Muqsith Barru
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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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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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