A hard-coded cryptographic key is used by Altium Enterprise Server to sign file download URLs in the Vault service. Because the key is identical across all installations, an unauthenticated network attacker who can reach the server can forge valid download signatures and retrieve files from the Vault storage area without any authentication, session, or credentials. A separate path traversal vulnerability in the same download endpoint allows the configured storage root to be escaped, enabling reads of arbitrary files on the server filesystem. Combined, these issues allow an unauthenticated attacker to obtain sensitive server configuration and key material, which can lead to full server compromise. The vulnerability can be chained with CVE-2026-9152 to enumerate and bulk-download stored content. Altium 365 cloud deployments are not impacted in practice, as file storage uses object storage rather than the local filesystem.