Replicate Cog: Server-Side Request Forgery vulnerability (CVE-2026-56712)

CVE-2026-56712 is a Server-Side Request Forgery (SSRF) vulnerability affecting the Replicate Cog library. The cog.types.File.validate() and cog.types.Path.validate() functions fail to perform destination validation when processing user-provided HTTP(S) URLs. Because the library uses the requests library with default settings, it automatically follows redirects, allowing an attacker to reach internal or loopback resources by first contacting an attacker-controlled redirector. A public proof-of-concept exists, though no active exploitation has been confirmed.

Impact

Successful exploitation allows an unauthenticated attacker to make requests to internal services, local loopback resources (e.g., administrative interfaces, internal APIs), and cloud metadata services (e.g., 169.254.169.254), which could lead to unauthorized information disclosure.

Recommendation

• Upgrade Cog to a version incorporating the fix described in the provided fix.md.
• If upgrading is not immediately feasible, ensure that any user-controlled input to cog.File or cog.Path is strictly validated against a known allowlist of domains or CIDRs.
• Implement a dedicated fetch proxy that enforces hostname resolution validation, disables automatic redirects, and blocks private/loopback address ranges (including 169.254.169.254).