# CVE-2026-102803: Joomla Extension - j2commerce.com - Gift voucher and single-use coupon could pay for more than one order in J2Store 6.0.0 - 6.6.5

Status: published. Published: 2026-11-10. Updated: 2026-11-10.

Joomla Extension - j2commerce.com - Gift voucher and single-use coupon could pay for more than one order in J2Store 6.0.0 - 6.6.5 - A logged-in customer could redeem a single gift voucher, or a single-use coupon (`max_uses` / `max_customer_uses` = 1), on more than one order. By starting several checkout sessions and carrying each to the confirm step before submitting any of them, every order independently saw the voucher's full balance or the coupon's unused slot, because the balance/usage calculations and the final placement check both only looked at orders that had already left the "New" state.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- j2commerce.com / J2Store extension for Joomla: 6.0.0-6.6.5 (affected). Source: CNA: Joomla

## Severity and prioritization

- CVSS 4.0: 6 (medium); CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N; source: CNA: Joomla

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-367

## Exploit evidence

No exploit evidence in collected sources. This is not proof of no exploitation.

## References

- https://www.j2commerce.com/ (CNA: Joomla; product)

## Provenance

- CNA: Joomla: https://www.cve.org/CVERecord?id=CVE-2026-102803; retrieved 2026-11-10; source updated 2026-11-10

Revision: 13c9fc6e2507c9e7a10e27cfe6c9aed90d4bfd832b0e27dfd3021e7b0e487aa3

Canonical: https://y2.dev/cve/CVE-2026-102803

## Agent and API access

Public CVE pages, Markdown, and JSON are free to read without an account or API key.

- Public catalog: https://y2.dev/cve/index.json. Follow nextCursor with the same search, filters, sort, and limit (1–100). A null cursor marks the end.

- WebMCP: search_cve_disclosures, get_cve_disclosure, get_cve_page_markdown, get_y2_cve_access. Available in compatible browsers.

- Cyber API: https://api.y2.dev/api/v2/cyber/cves and https://api.y2.dev/api/v2/cyber/cves/{cveId}.

- Y2 Pro or Elite: create a workspace API key with the intel:cyber scope and send Authorization: Bearer <Y2_API_KEY>. Setup: https://y2.dev/docs/api/create-key.

- x402: Pay per request without an account or API key. Omit Authorization, read the HTTP 402 PAYMENT-REQUIRED challenge, validate its current requirements, and retry with PAYMENT-SIGNATURE through an authorized payment client. These browser tools never make payments. Guide: https://y2.dev/docs/api/x402.

- OpenAPI: https://y2.dev/api/openapi.yaml. Agent access metadata: https://y2.dev/cve/agent.json.

Collected public records only. Check source status for coverage and freshness.