Quick answers
- Is CVE-2026-103339 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-103339 being exploited in the wild.
- How severe is CVE-2026-103339?
- Medium severity, with a CVSS score of 6.5, published 1 October 2026.
- Which products and versions are affected?
- Wpmet Metform through 4.3.0.
- Is there a fix for CVE-2026-103339?
- Yes: fixed in 4.3.1. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-103339 attacked?
- It is attacked over the network, in a web application.
- Am I affected by CVE-2026-103339?
- Check whether you run Wpmet Metform 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.
How to fix
- Fixed in: 4.3.1
Technical details
This stored XSS vulnerability in Metform allows authenticated users with contributor or developer privileges to inject malicious JavaScript into form elements. The injected scripts are then executed in the browsers of site visitors who interact with the affected forms. Exploitation requires user interaction (victim must visit a crafted page or interact with the form) and valid account credentials, but once injected, the payload persists and affects all subsequent visitors.
Affected products
- Wpmet Metform through 4.3.0
Timeline
- 2026-09-25: disclosed: Reported by Intrudify
- 2026-10-01: advisory: Published by Patchstack