CVE-2026-4895

MEDIUM

Greenshift <= 12.8.9 - Authenticated (Contributor+) Stored Cross-Site Scripting via disablelazy Attribute

Title source: cna
STIX 2.1

Description

The GreenShift - Animation and Page Builder Blocks plugin for WordPress is vulnerable to Stored Cross-Site Scripting in versions up to, and including, 12.8.9 This is due to insufficient input sanitization and output escaping in the gspb_greenShift_block_script_assets() function. The function uses str_replace() to insert 'fetchpriority="high"' before 'src=' attributes when processing greenshift-blocks/image blocks with the disablelazy attribute enabled. Because this replacement operates on the entire HTML string without parsing, contributors can inject the string 'src=' into HTML attribute values (such as class attributes). When the str_replace executes, the double quotes in the replacement string break out of the attribute context, allowing injection of malicious HTML attributes like onfocus with JavaScript payloads. 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.

Scores

CVSS v3 6.4
EPSS 0.0042
EPSS Percentile 33.5%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-79
Status published
Products (1)
wpsoul/Greenshift – animation and page builder blocks < 12.8.9
Published Apr 11, 2026
Tracked Since Apr 11, 2026