CVE-2026-28803
Last modified
CVE-2026-28803 is a medium-severity vulnerability rated 6.5/10 on the CVSS scale. Open Forms allows users create and publish smart forms. Prior to 3.3.13 and 3.4.5, to be able to cosign, the cosigner receives an e-mail with instructions or a deep-link to start the cosign flow. EPSS estimates a 0.20% chance of exploitation in the next 30 days.
Description
Open Forms allows users create and publish smart forms. Prior to 3.3.13 and 3.4.5, to be able to cosign, the cosigner receives an e-mail with instructions or a deep-link to start the cosign flow. The submission reference is communicated so that the user can retrieve the submission to be cosigned. Attackers can guess a code or modify the received code to look up arbitrary submissions, after logging in (with DigiD/eHerkenning/... depending on form configuration). This vulnerability is fixed in 3.3.13 and 3.4.5.
Metrics
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Maykinmedia | Open Forms | < 3.3.13 |
| Maykinmedia | Open Forms | >= 3.4.0, < 3.4.5 |
References
- https://github.com/open-formulieren/open-forms/security/advisories/GHSA-2g49-rfm6-5qj5Mitigation, Vendor Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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