CVE-2026-28803: medium-severity vulnerability in open-formulieren open-forms
Open Forms possible to view submission details of other people than intended
Published
E-mail alert when it lands in KEV, gets a public PoC or its score goes up.
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.5epss 0.2%
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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected products
open-formulieren · open-formsRelated CVEs — open-formulieren open-forms
In the same product, most dangerous first.
CVE-2022-31041HIGHInsufficient content-type validation for uploaded files in open-formsEPSS 0.8%CVE-2022-31040HIGHOpen Redirect in open-formsEPSS 0.7%CVE-2024-24771HIGHOpen Forms potential multi-factor authentication bypassEPSS 0.6%CVE-2025-64515MEDIUMOpen Forms prefill data in read-only components can be tamperedEPSS 0.3%