Executive brief
Sonatype Nexus Repository 3 is a popular artifact management system used to store and manage software dependencies and build artifacts. An authorization flaw in the blobstore group management REST API endpoints allows users with limited "create" permissions to perform "update" operations on blobstore configurations, bypassing intended security controls. This could enable unauthorized modification of critical storage infrastructure without administrator approval.
Technical details
This is an authorization bypass vulnerability affecting the blobstore group management REST API endpoints in Nexus Repository 3. The root cause is insufficient permission enforcement: two endpoints do not correctly validate that the user holds the nexus:blobstores:update permission before allowing conversion of an existing blobstore into a group blobstore. An attacker who has been granted the lower-privilege nexus:blobstores:create permission (which must be explicitly assigned) can invoke these endpoints to perform operations that should require the nexus:blobstores:update permission instead. The attack is network-accessible and requires only valid authentication credentials with the create permission. The fix is available in patched versions of Nexus Repository 3.
Affected products
- Sonatype Nexus Repository 3 3.x (prior to patched versions in 3.96.0+)
Timeline
- 2026-09-02: disclosed