Kargo: SSRF in Promotion http/http-download Steps Enables Internal Network Access and Data Exfiltration

Kargo manages and automates the promotion of software artifacts. In versions 1.4.0 through 1.6.3, 1.7.0-rc.1 through 1.7.8, 1.8.0-rc.1 through 1.8.11, and 1.9.0-rc.1 through 1.9.4, the http and http-download promotion steps allow Server-Side Request Forgery (SSRF) against link-local addresses, most critically the cloud instance metadata endpoint (169.254.169.254), enabling exfiltration of sensitive data such as IAM credentials. These steps provide full control over request headers and methods, rendering cloud provider header-based SSRF mitigations ineffective. An authenticated attacker with permissions to create/update Stages or craft Promotion resources can exploit this by submitting a malicious Promotion manifest, with response data retrievable via Promotion status fields, Git repositories, or a second http step. This issue has been fixed in versions 1.6.4, 1.7.9, 1.8.12 and 1.9.5.