CVE-2026-75106: Opnform

Critical severity, CVSS 9.1. EPSS: 0.4% chance of exploitation in the next 30 days.

OpnForm derives editable-submission secrets from sequential row identifiers using Hashids with an empty default salt, allowing unauthenticated attackers to compute hashes for any submission. Attackers can read other respondents' full submission data through the submission-fetch endpoint or overwrite submissions by supplying predicted hashes to the answer endpoint.

Affected products

• Opnform Opnform: before 2.0.2 (fixed in 2.0.2)

Published 2026-08-17. Last modified 2026-10-01.