CVE-2026-28803

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 v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/open-formulieren/open-forms/security/advisories/GHSA-2g49-rfm6-5qj5	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:maykinmedia:open_forms::::::::
	cpe:2.3:a:maykinmedia:open_forms::::::::

History

No history.

Information

Published : 2026-03-11 16:16

Updated : 2026-03-17 19:19

NVD link : CVE-2026-28803

Mitre link : CVE-2026-28803

CVE.ORG link : CVE-2026-28803

JSON object : View

Products Affected

maykinmedia

open_forms

CWE

CWE-284

Improper Access Control

NVD-CWE-noinfo

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