What is the CVSS score of CVE-2026-40770?

CVE-2026-40770 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 Coupon Affiliates are affected by CVE-2026-40770?

Coupon Affiliates WordPress plugin (versions up to 7.5.3) contains an unauthenticated cross-site scripting vulnerability that allows attackers to compromise user sessions and inject malicious code…

How to fix or mitigate CVE-2026-40770?

Within 24 hours: Inventory all WordPress instances running Coupon Affiliates plugin versions ≤7.5.3; prioritize business-critical affiliate systems. Within 7 days: Deploy WAF rules blocking XSS payloads in plugin endpoints; implement strict Content Security Policy (CSP) headers; disable the plugin on non-production instances if operationally feasible. Within 30 days: Monitor Coupon Affiliates vendor advisory page and WordPress.org plugin repository daily for security updates; develop contingency plan to replace the plugin with a patched alternative if no fix is released within 90 days.

Coupon Affiliates CVE-2026-40770

EUVD-2026-36979 HIGH

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

2026-06-15 Patchstack

GHSA-gm96-jpjv-4px7

XSS Coupon Affiliates

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 WordPress plugin endpoint, no attacker auth, but victim click required; XSS in admin origin gives scope change with limited C/I/A impact.

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:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N

Primary rating from Vendor (Patchstack).

CVSS VectorVendor: Patchstack

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

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 - 22:11 vuln.today

DescriptionCVE.org

Unauthenticated Cross Site Scripting (XSS) in Coupon Affiliates <= 7.5.3 versions.

AnalysisAI

Unauthenticated reflected/stored cross-site scripting in the Coupon Affiliates WordPress plugin (versions up to and including 7.5.3) allows remote attackers to inject malicious script that executes in a victim's browser after user interaction. The CVSS 3.1 score of 7.1 with scope change (S:C) indicates impact beyond the vulnerable component, typical of XSS reaching the WordPress admin or affiliate context. No public exploit identified at time of analysis, and the issue is not listed in CISA KEV.

Technical ContextAI

Coupon Affiliates (formerly Woo Coupon Usage, plugin slug 'woo-coupon-usage') is a WordPress/WooCommerce plugin from RelyWP that lets store owners assign coupons to affiliates and track usage. The CPE 'cpe:2.3:a:relywp:coupon_affiliates' identifies the affected vendor and product. The root cause is CWE-79 (Improper Neutralization of Input During Web Page Generation), meaning the plugin emits attacker-controlled data into HTML responses without adequate output encoding or input sanitization. The Patchstack advisory categorizes it under the woo-coupon-usage plugin database entry, indicating the flaw resides in a plugin-rendered view rendered to either affiliates or store administrators.

RemediationAI

Upgrade the Coupon Affiliates plugin to a version newer than 7.5.3 once available from the vendor; consult the Patchstack advisory at https://patchstack.com/database/wordpress/plugin/woo-coupon-usage/vulnerability/wordpress-coupon-affiliates-plugin-7-5-3-cross-site-scripting-xss-vulnerability for the fixed release. The input does not specify an exact fixed version, so released patched version not independently confirmed - verify with the plugin's WordPress.org changelog before deploying. As compensating controls while patching, deploy a Web Application Firewall (e.g., Patchstack mU plugin or Wordfence) with virtual patching rules for this CVE, enforce a strict Content-Security-Policy that disallows inline script execution on WooCommerce admin pages (side effect: may break admin features relying on inline JS), and temporarily deactivate the plugin if the affiliate functionality is not business-critical (side effect: affiliate tracking and coupon attribution will stop working).