Quick answers
- Is CVE-2026-87091 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-87091 being exploited in the wild.
- How severe is CVE-2026-87091?
- High severity, with a CVSS score of 7.2, published 3 October 2026.
- Which products and versions are affected?
- Welcart e-Commerce up to and including 2.12.2.
- Is there a fix for CVE-2026-87091?
- No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
- How is CVE-2026-87091 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-87091?
- Check whether you run Welcart e-Commerce at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The IPN (Instant Payment Notification) endpoint accepts the 'rel' and 'option' parameters without authentication, nonce validation, or signature verification, and stores them unsanitized in the settlement error log. When administrators access the error log view, these parameters are rendered without proper output escaping, triggering stored XSS. An unauthenticated attacker can directly submit malicious payloads that persist in the database and execute in the admin context.
Affected products
- Welcart e-Commerce up to and including 2.12.2
Timeline
- 2026-10-03: disclosed