CVE-2026-34750: Payloadcms Payload

Medium severity, CVSS 6.5. EPSS: 0.4% chance of exploitation in the next 30 days.

Payload is a free and open source headless content management system. Prior to version 3.78.0 in @payloadcms/storage-azure, @payloadcms/storage-gcs, @payloadcms/storage-r2, and @payloadcms/storage-s3, the client-upload signed-URL endpoints for S3, GCS, Azure, and R2 did not properly sanitize filenames. An attacker could craft filenames to escape the intended storage location. This issue has been patched in version 3.78.0 for @payloadcms/storage-azure, @payloadcms/storage-gcs, @payloadcms/storage-r2, and @payloadcms/storage-s3.

Affected products

• Payloadcms Payload: before 3.78.0 (fixed in 3.78.0)

Published 2026-04-01. Last modified 2026-06-17.