Spectra Gutenberg Blocks <= 2.19.28 - Authenticated (Contributor+) Stored Cross-Site Scripting via uagb/image Block

2026-07-20 09:16

theviper17y

Strategic Overview

Status

Patched in 2.19.29

Affected PluginSpectra Legacy – Gutenberg Blocks

Affected Version<= 2.19.28

CVSS6.4Medium

CVECVE-2026-12900

View all Spectra Legacy – Gutenberg Blocks vulnerabilities

Vulnerability Overview

The Spectra Gutenberg Blocks – Website Builder for the Block Editor plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the `uagb/image` block in all versions up to, and including, 2.19.28 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with Contributor-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page.

Technical Analysis

REMEDIATION: Update to version 2.19.29, or a newer patched version --- IDENTIFIER: CWE-79 (Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')) The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

External References

https://www.cve.org/CVERecord?id=CVE-2026-12900 https://www.wordfence.com/threat-intel/vulnerabilities/id/0e9dc5e3-9d72-4c04-8ba9-56428a6fdddd

CVSS Vector

6.4

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

Base

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow
User InteractionNone
ScopeChanged
ConfidentialityLow
IntegrityLow
AvailabilityNone

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