How to fix CVE-2024-45337 – Step-by-Step Guide
CVE-2024-45337 addresses a critical vulnerability in Go's crypto/ssh library. This flaw, named "Misuse of ServerConfig.PublicKeyCallback," can lead to unauthorized SSH authentication bypass in affected Go applications. It's crucial to update to mitigate this severe risk.
What is Go crypto/ssh – Misuse of ServerConfig.PublicKeyCallback?
CVE-2024-45337 stems from a logic flaw in Go's crypto/ssh ServerConfig.PublicKeyCallback. Applications using this callback may incorrectly authorize connections even if the key is approved but subsequent authentication fails. This bypasses intended security checks, allowing unauthorized access to SSH servers.
Impact and Risks for your Infrastructure
This critical vulnerability enables attackers to bypass SSH authentication in Go applications. Successful exploitation grants unauthorized access to sensitive systems, potentially leading to data breaches, full system compromise, and significant operational disruption. Immediate action is required to protect your infrastructure.
Step-by-Step Mitigation Guide
To mitigate CVE-2024-45337, update your Go applications to versions 1.22.10+ or 1.23.4+. Verify the fix by ensuring your Go environment uses one of the patched versions. Rebuild and redeploy any affected services to apply the security update effectively.
- 1Upgrade Go to 1.22.10+ or 1.23.4+.
- 2Review your PublicKeyCallback implementation to ensure it rejects unauthorized keys.
- 3Add explicit key allowlist validation inside PublicKeyCallback.
- 4Rotate SSH host keys and audit SSH access logs for anomalies.
- 5Run static analysis (govulncheck) to detect usage of vulnerable patterns.
- 6Pin allowed public keys in your callback rather than relying on post-callback checks.