What is the CVSS score of CVE-2026-4895?

CVE-2026-4895 has a CVSS 3.1 base score of 6.4 (Medium). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N. EPSS exploitation probability: 0.0%.

Greenshift Animation And Page Builder Blocks CVE-2026-4895

EUVD-2026-21647 MEDIUM

Cross-site Scripting (XSS) (CWE-79)

2026-04-11 Wordfence

WordPress XSS Greenshift Animation And Page Builder Blocks Wordpress Plugin Wpsoul

6.4

CVSS 3.1 · NVD

Severity by source

NVD PRIMARY

6.4 MEDIUM

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

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Lifecycle Timeline

EUVD ID Assigned

Apr 11, 2026 - 01:30 euvd

EUVD-2026-21647

Analysis Generated

Apr 11, 2026 - 01:30 vuln.today

CVE Published

Apr 11, 2026 - 01:24 nvd

MEDIUM 6.4

DescriptionCVE.org

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.

AnalysisAI

Stored cross-site scripting in GreenShift - Animation and Page Builder Blocks plugin for WordPress up to version 12.8.9 allows authenticated contributors to inject arbitrary JavaScript into pages via improper HTML string manipulation in the gspb_greenShift_block_script_assets() function. The vulnerability exploits a naive str_replace() operation that fails to parse HTML context, enabling attackers to break out of attribute boundaries and inject malicious event handlers like onfocus with JavaScript payloads that execute when users access affected pages. No public exploit code has been identified; however, the low attack complexity and straightforward injection vector make this a practical risk for sites with untrusted contributors.

Technical ContextAI

The vulnerability resides in the gspb_greenShift_block_script_assets() function within the GreenShift WordPress plugin (CPE: cpe:2.3:a:wpsoul:greenshift_-_animation_and_page_builder_blocks:*:*:*:*:*:*:*:*), which processes greenshift-blocks/image blocks when the disablelazy attribute is enabled. The function uses PHP's str_replace() to insert the string 'fetchpriority="high"' before 'src=' attributes in HTML markup. This approach treats HTML as plain text rather than parsing it into a structured DOM, which is fundamentally insecure. An authenticated attacker with contributor-level privileges can craft block parameters containing the literal string 'src=' embedded within HTML attribute values (for example, in a class attribute like class="src="onclick="alert(1)"). When str_replace() processes the full HTML string, it matches this embedded 'src=' substring and performs the replacement, inserting 'fetchpriority="high"' before it. The double-quote characters in the replacement string then break out of the surrounding attribute context, allowing the injection of additional HTML attributes such as onfocus with inline JavaScript. This is classified as CWE-79 (Improper Neutralization of Input During Web Page Generation, also known as Cross-site Scripting), specifically a stored XSS variant because the malicious payload is persisted in the WordPress database and executed for all subsequent visitors.

RemediationAI

The primary remediation is to upgrade the GreenShift - Animation and Page Builder Blocks plugin to version 12.9.0 or later, which contains the patched code that properly handles HTML attribute insertion. Site administrators should update immediately via the WordPress plugin dashboard (Plugins > Installed Plugins > GreenShift > Update). As a temporary workaround pending upgrade, site owners can restrict contributor-level access to only trusted staff and disable the greenshift-blocks/image block with the disablelazy attribute enabled if it is not essential to site operations, though these measures do not eliminate the vulnerability. The vulnerability fix is documented in the WordPress plugin repository changeset at https://plugins.trac.wordpress.org/changeset/3494855/greenshift-animation-and-page-builder-blocks/trunk/init.php, which shows the replacement of the naive str_replace() logic with proper HTML parsing or escaped attribute construction.