Description
Joomla Extension - j2commerce.com - Stored XSS in Guest checkout in J2Store 1.0.0-3.3.20, 4.0.0-4.0.20, 4.1.0-4.1.5 - J2Commerce 4.1.5 is vulnerable to Stored Cross-Site Scripting (XSS) through the guest checkout billing address fields. An unauthenticated attacker exploits a filter bypass in Joomla's Input::getArray() combined with PHP's variables_order=EGPCS (Cookie overrides POST in $_REQUEST ) to store unsanitized HTML in fields such as billing_first_name.
Published: 2026-08-21
Score: 8.6 High
EPSS: < 1% Very Low
KEV: No
Impact: Stored Cross‑Site Scripting
Action: Patch
AI Analysis

Impact

The vulnerability allows an unauthenticated attacker to store arbitrary HTML in the guest checkout billing address fields, enabling the execution of malicious JavaScript when site visitors view the affected content; this results in cross‑site scripting with potential theft of credentials, session hijacking, or defacement. The flaw is a classic example of CWE‑79: Improper Neutralization of Input During Web Page Generation.

Affected Systems

J2Store extension for Joomla, versions 1.0.0 through 3.3.20, 4.0.0 through 4.0.20, and 4.1.0 through 4.1.5, are affected.

Risk and Exploitability

With a CVSS score of 8.6 the weakness is considered high severity. The EPSS score is not available, so the probability of exploitation cannot be quantified currently, and the vulnerability is not listed in the CISA KEV catalog. The likely attack vector is an unauthenticated user submitting a guest checkout form on a public e‑commerce site, a scenario that is common for many installations.

Generated by OpenCVE AI on August 21, 2026 at 20:44 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Upgrade J2Store to version 4.1.6 or later, which removes the input sanitization flaw.
  • Reconfigure PHP so that variables_order does not include EGPCS, preventing cookie overrides of POST data.
  • Sanitize all billing address fields during input processing and escape output before rendering to mitigate XSS.
  • If an immediate upgrade is not possible, apply temporary filtering of stored content on the front end to reduce the risk of malicious script execution.

Generated by OpenCVE AI on August 21, 2026 at 20:44 UTC.

Tracking

Sign in to view the affected projects.

Advisories

No advisories yet.

References
Link Providers
https://www.j2commerce.com/ cve-icon cve-icon
History

Fri, 21 Aug 2026 21:45:00 +0000

Type Values Removed Values Added
First Time appeared J2commerce.com
J2commerce.com j2store Extension For Joomla
Vendors & Products J2commerce.com
J2commerce.com j2store Extension For Joomla

Fri, 21 Aug 2026 20:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Fri, 21 Aug 2026 19:30:00 +0000

Type Values Removed Values Added
Description Joomla Extension - j2commerce.com - Stored XSS in Guest checkout in J2Store 1.0.0-3.3.20, 4.0.0-4.0.20, 4.1.0-4.1.5 - J2Commerce 4.1.5 is vulnerable to Stored Cross-Site Scripting (XSS) through the guest checkout billing address fields. An unauthenticated attacker exploits a filter bypass in Joomla's Input::getArray() combined with PHP's variables_order=EGPCS (Cookie overrides POST in $_REQUEST ) to store unsanitized HTML in fields such as billing_first_name.
Title Joomla Extension - j2commerce.com - Stored XSS in Guest checkout in J2Store 1.0.0-3.3.20, 4.0.0-4.0.20, 4.1.0-4.1.5
Weaknesses CWE-79
References
Metrics cvssV4_0

{'score': 8.6, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N'}

Subscriptions

J2commerce.com J2store Extension For Joomla
cve-icon MITRE

Status: PUBLISHED

Assigner: Joomla

Published:

Updated: 2026-08-21T20:09:07.770Z

Reserved: 2026-08-15T04:38:57.663Z

Link: CVE-2026-74252

cve-icon Vulnrichment

Updated: 2026-08-21T20:05:57.817Z

cve-icon NVD

Status : Deferred

Published: 2026-08-21T20:16:41.000

Modified: 2026-08-26T16:35:20.160

Link: CVE-2026-74252

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-08-21T21:14:48Z

Weaknesses
  • CWE-79

    Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')