CVE-2026-28803
Open Forms possible to view submission details of other people than intended
CVSS Score
6.5
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-284 |
| Vendor | open-formulieren |
| Product | open-forms |
| Published | Mar 11, 2026 |
| Last Updated | Mar 11, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Affected Versions
open-formulieren / open-forms
>= 3.4.0-alpha.0, < 3.4.5 < 3.3.13