CVE-2026-8981 (GCVE-0-2026-8981)

Vulnerability from cvelistv5 – Published: 2026-06-09 06:00 – Updated: 2026-06-09 10:32
VLAI
Title
Lazy Blocks < 4.3.0 - Admin+ Stored XSS via Custom Block Frontend HTML
Summary
The Custom Block Builder WordPress plugin before 4.3.0 does not consistently check the unfiltered_html capability across all paths that write to its block template code fields, allowing administrators on multisite installations (or single-site installs with DISALLOW_UNFILTERED_HTML defined) to inject arbitrary JavaScript that executes for any visitor of pages embedding the affected block.
Severity
3.5 (Low)
CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
URL Tags
https://wpscan.com/vulnerability/9815b0e6-e411-4a… exploitvdb-entrytechnical-description
Impacted products
Vendor Product Version
Unknown Custom Block Builder Affected: 0 , < 4.3.0 (semver)
Create a notification for this product.
Credits
Luca Jungnickel WPScan
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • 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.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • 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.


Detection rules are retrieved from Rulezet.