CVE-2026-59387
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk14th percentile - higher than 14% of all known CVEs
Summary
The Nginx routing configuration for Cloud Controller blocks unauthenticated access to /internal/v4/ and /internal/v5/ endpoints but omits an equivalent deny rule for /internal/v3/. As a result, the staging callback endpoints /internal/v3/staging/:guid/droplet_completed and /internal/v3/staging/:guid/build_completed are reachable from the public API listener without OAuth or mutual TLS.
Risk Assessment
An attacker with a valid build or droplet GUID can submit a forged staging callback, transition a droplet to STAGED, and persist arbitrary process metadata and sidecar data with no associated package or actor. A SpaceAuditor can enumerate GUIDs without write permissions, making this an effective privilege escalation beyond the intended role boundary.
Recommendation
Add a deny rule for /internal/v3/ in the Cloud Controller Nginx configuration equivalent to those for /internal/v4/ and /internal/v5/, and verify that staging endpoints are not reachable from the public API listener.
Other vulnerabilities in Cloud Controller (CAPI)
Original NVD description (English source)
The Nginx routing configuration for Cloud Controller blocks unauthenticated access to /internal/v4/ and /internal/v5/ endpoints but omits an equivalent deny rule for /internal/v3/. As a result, the staging callback endpoints /internal/v3/staging/:guid/droplet_completed and /internal/v3/staging/:guid/build_completed are reachable from the public API listener without OAuth or mutual TLS. An attacker with a valid build or droplet GUID can submit a forged staging callback, transition a droplet to STAGED, and persist arbitrary process metadata and sidecar data with no associated package or actor. A SpaceAuditor can enumerate GUIDs without write permissions, making this an effective privilege escalation beyond the intended role boundary.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

