What is the CVSS score of EUVD-2026-36859?

EUVD-2026-36859 has a CVSS 3.1 base score of 7.1 (High). CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:L. EPSS exploitation probability: 0.2%.

Which versions of HollerBox are affected by EUVD-2026-36859?

HollerBox WordPress plugin versions 2.3.10.1 and earlier contain a stored/reflected cross-site scripting vulnerability allowing unauthenticated attackers to inject malicious code that executes in…

How to fix or mitigate EUVD-2026-36859?

Within 24 hours: Inventory all WordPress instances running HollerBox version 2.3.10.1 or earlier and classify by business criticality. Within 7 days: Disable and uninstall HollerBox on all production systems; procure and deploy alternative notification/popup plugin with active security maintenance. Within 30 days: Implement Web Application Firewall (WAF) rules for any legacy systems that cannot be immediately patched, establish CSP headers, and set up monitoring for patch availability from vendor.

HollerBox EUVD-2026-36859

| CVE-2026-48885 HIGH

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

2026-06-15 Patchstack

GHSA-j36x-g5wc-m7vg

WordPress XSS Groundhogg Wordpress Plugin Hollerbox

7.1

CVSS 3.1 · Vendor: Patchstack

Severity by source

Vendor (Patchstack) PRIMARY

7.1 HIGH

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

vuln.today AI

7.1 HIGH

Network-reachable unauthenticated XSS requiring victim interaction; scope changes to browser/site context with low confidentiality, integrity, and availability impact via injected script.

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

4.0 AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Primary rating from Vendor (Patchstack).

CVSS VectorVendor: Patchstack

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

Low

Lifecycle Timeline

Analysis Generated

Jun 15, 2026 - 21:44 vuln.today

DescriptionCVE.org

Unauthenticated Cross Site Scripting (XSS) in HollerBox <= 2.3.10.1 versions.

AnalysisAI

Unauthenticated reflected/stored cross-site scripting in the HollerBox WordPress plugin (versions 2.3.10.1 and earlier) allows remote attackers to inject malicious JavaScript that executes in a victim's browser when they interact with a crafted link or page. The flaw was disclosed via Patchstack and carries a CVSS 3.1 score of 7.1 due to the scope change (S:C) reflecting the WordPress site context being affected from injected content; no public exploit identified at time of analysis and no CISA KEV listing exists.

Technical ContextAI

HollerBox (also known as Holler Box) is a WordPress plugin by Groundhogg used to display popups, notification bars, and lead-capture widgets on WordPress sites; the affected CPE is cpe:2.3:a:groundhogg:hollerbox:*. The root cause is CWE-79 (Improper Neutralization of Input During Web Page Generation), meaning user-supplied data is rendered into HTML/JS contexts without proper output encoding or input sanitization, allowing script injection. Because the CVSS vector includes S:C (scope changed), the executed script runs in the trust context of the WordPress site, enabling cross-origin impact such as session theft or admin-session abuse if an authenticated administrator triggers the payload.

RemediationAI

Upgrade the HollerBox plugin to a version newer than 2.3.10.1 once the vendor publishes a fixed release; the Patchstack advisory at https://patchstack.com/database/wordpress/plugin/holler-box/vulnerability/wordpress-hollerbox-plugin-2-3-10-1-cross-site-scripting-xss-vulnerability should be consulted for the exact fixed version, as no specific patched version was supplied in this intelligence. As compensating controls until patched, deploy a WordPress WAF rule (e.g., Patchstack, Wordfence) that filters script tags and JavaScript event handlers on HollerBox endpoints, deactivate the HollerBox plugin if it is not in active use (eliminates the attack surface entirely but removes popup/notification functionality), and enforce a strict Content-Security-Policy header that disallows inline scripts (may break legitimate inline JS in themes/plugins and requires testing). Administrators should also avoid clicking unknown links to their own site while authenticated, since admin-session interaction is what makes XSS dangerous.