CVE-2026-24408: Linuxfoundation Sigstore-Python

Medium severity, CVSS 5.0. EPSS: 0.2% chance of exploitation in the next 30 days.

sigstore-python is a Python tool for generating and verifying Sigstore signatures. Prior to version 4.2.0, the sigstore-python OAuth authentication flow is susceptible to Cross-Site Request Forgery. `_OAuthSession` creates a unique "state" and sends it as a parameter in the authentication request but the "state" in the server response seems not not be cross-checked with this value. Version 4.2.0 contains a patch for the issue.

Affected products

• Linuxfoundation Sigstore-Python: before 4.2.0 (fixed in 4.2.0)

Published 2026-01-26. Last modified 2026-06-17.