How the CVE Works:
The vulnerability in Vela Server (CVE-2025-XXXX) stems from insufficient verification of webhook payload data. Attackers can exploit this flaw by crafting a malicious webhook payload with specific headers and body data. When processed by the server, this payload can manipulate repository ownership and exfiltrate repository-level CI secrets. This is particularly dangerous for users with enabled repositories and access to CI secrets, as it allows unauthorized transfer of sensitive data to external repositories. The issue affects Vela Server versions < 0.25.3 and >= 0.26.0, < 0.26.2. Patched versions (0.25.3 and 0.26.3) address this by implementing proper payload verification.
DailyCVE Form:
Platform: Vela Server
Version: < 0.25.3, >= 0.26.0, < 0.26.2
Vulnerability: Insufficient Webhook Payload Verification
Severity: Critical
Date: Mar 10, 2025
What Undercode Say:
Exploitation:
1. Crafting Malicious Payload:
Attackers can use tools like `curl` or Python scripts to send spoofed webhook payloads.
Example Payload:
{
"repository": "attacker/repo",
"headers": {
"X-GitHub-Event": "push",
"X-Hub-Signature": "spoofed_signature"
},
"body": {
"action": "transfer_ownership",
"target_repo": "attacker/repo"
}
}
2. Sending Payload:
Use `curl` to send the payload to the Vela Server endpoint:
curl -X POST -H "Content-Type: application/json" -d @malicious_payload.json http://vela-server/webhook
3. Exfiltrating Secrets:
Once ownership is transferred, attackers can trigger builds to exfiltrate secrets.
Protection:
1. Upgrade:
Update to patched versions (0.25.3 or 0.26.3):
docker pull target/vela-server:v0.26.3
2. Payload Verification:
Implement custom middleware to verify webhook payloads:
import hmac import hashlib def verify_payload(secret, payload, signature): computed_signature = hmac.new(secret.encode(), payload, hashlib.sha256).hexdigest() return hmac.compare_digest(computed_signature, signature)
3. Restrict Access:
Limit repository access and CI secret permissions to trusted users only.
4. Monitor Logs:
Regularly monitor webhook logs for unusual activity:
tail -f /var/log/vela-server/webhook.log
5. Network Security:
Use firewalls to restrict access to the Vela Server webhook endpoint:
iptables -A INPUT -p tcp --dport 8080 -s trusted_ip -j ACCEPT iptables -A INPUT -p tcp --dport 8080 -j DROP
6. Secret Rotation:
Rotate CI secrets regularly to minimize exposure.
By following these steps, users can mitigate the risk of exploitation and secure their Vela Server instances.
References:
Reported By: https://github.com/advisories/GHSA-9m63-33q3-xq5x
Extra Source Hub:
Undercode
