CVE-2026-105867: @payloadcms Storage-s3

High severity, CVSS 7.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Payload is a free and open source headless content management system. In @payloadcms/storage-s3 versions before 3.90.0 and canary versions before 4.0.0-canary.34, an authenticated user can overwrite an existing S3 object belonging to another upload collection when client uploads are enabled for multiple collections sharing a bucket and useCompositePrefixes is false or unset. This bypasses the target collection's access controls and prior file validation. This issue is fixed in versions 3.90.0 and 4.0.0-canary.34.

Affected products

• @payloadcms Storage-s3: before 3.90.0 (fixed in 3.90.0); from 4.0.0-canary.0, before 4.0.0-canary.34 (fixed in 4.0.0-canary.34)
• Payloadcms Payload: before 3.90.0 (fixed in 3.90.0); from 4.0.0-canary.0, before 4.0.0-canary.34 (fixed in 4.0.0-canary.34)

Published 2026-10-06. Last modified 2026-10-06.