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How the CVE Works
The vulnerability (CVE-2023-XXXX) in Steve arises due to improper TLS certificate validation during remote server connections. By default, Steve does not verify the authenticity of the server’s TLS certificate, enabling Man-in-the-Middle (MitM) attacks. An attacker intercepting the connection can present a forged certificate, leading to unauthorized data access or UI manipulation. In Rancher’s case, if `ui-offline-preferred` is set to remote, an attacker with service creation privileges can hijack the UI, inject malicious scripts (XSS), or steal credentials. The flaw stems from Go’s TLS configuration not enforcing strict certificate checks.
DailyCVE Form
Platform: Steve
Version: <v0.2.1, v0.3.3, v0.4.4, v0.5.13
Vulnerability: TLS bypass
Severity: Critical
Date: YYYY-MM-DD
What Undercode Say:
Exploitation:
- MitM Setup: Use tools like `mitmproxy` to intercept Steve’s TLS traffic:
mitmproxy --mode transparent --ssl-insecure
- Certificate Spoofing: Generate a self-signed cert and inject it into the connection:
openssl req -x509 -newkey rsa:4096 -nodes -out fake.crt -keyout fake.key
- UI Hijacking: Deploy a malicious service in Rancher’s local cluster when
ui-offline-preferred=remote.
Protection:
1. Upgrade: Apply patches (v0.2.1/v0.3.3/v0.4.4/v0.5.13+).
- Enforce TLS: Configure Go to enforce strict validation:
tlsConfig := &tls.Config{ InsecureSkipVerify: false, // Disable insecure bypass } - Network Controls: Restrict Steve to trusted endpoints via firewall rules:
iptables -A OUTPUT -p tcp --dport 443 -d trusted-ip -j ACCEPT
4. Monitor: Log TLS handshake failures for anomalies:
grep "TLS handshake error" /var/log/steve.log
5. Rancher Hardening: Ensure `ui-offline-preferred` remains `dynamic`.
References:
Sources:
Reported By: github.com
Extra Source Hub:
Undercode
