CVE-2024-4655: Ultimate Blocks < 3.1.9 - Contributor+ Stored XSS

Severity: medium (CVSS 5.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2024-07-11 · updated 2026-06-17
Weakness: CWE-79

Description

The Ultimate Blocks WordPress plugin before 3.1.9 does not validate and escape some of its block options before outputting them back in a page/post where the block is embed, which could allow users with the contributor role and above to perform Stored Cross-Site Scripting attacks

Affected products

ultimateblocks Ultimate Blocks – 25+ Gutenberg Blocks for Block Editor: before 3.1.9 — fixed in 3.1.9

How to fix

Upgrade to a fixed version: ultimateblocks Ultimate Blocks – 25+ Gutenberg Blocks for Block Editor 3.1.9. Check the vendor advisory for mitigations.

References

https://wpscan.com/vulnerability/a0dc73b3-3c51-4d03-963f-00fa7d8b0d51/
https://wpscan.com/vulnerability/a0dc73b3-3c51-4d03-963f-00fa7d8b0d51/

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