Attack Chain

1. Attacker authenticates to the edx-enterprise instance as an Enterprise Admin.
2. Attacker sends a PATCH request to the SAMLProviderConfigViewSet to modify the metadata_source to a malicious URL (e.g., http://169.254.169.254/latest/meta-data/iam/security-credentials/).
3. The server stores the malicious URL in the SAMLProviderConfig.metadata_source field.
4. Attacker sends a POST request to the sync_provider_data endpoint.
5. The sync_provider_data function retrieves the metadata_source URL from the SAMLProviderConfig.
6. The fetch_metadata_xml function is called with the malicious URL.
7. fetch_metadata_xml uses requests.get() to make an HTTP request to the attacker-controlled URL.
8. The server attempts to parse the (likely invalid) XML response. Even if parsing fails, the attacker has successfully triggered an SSRF.

Impact

Successful exploitation of this SSRF vulnerability allows an Enterprise Admin to perform several malicious actions: steal cloud credentials by accessing instance metadata services (AWS, GCP, Azure), scan internal networks by probing hosts and ports behind the firewall, and access internal APIs not exposed to the internet. This can lead to full compromise of the cloud infrastructure and sensitive data exposure.

Recommendation

• Apply the recommended patch by upgrading edx-enterprise to a version outside the range of >= 7.0.2, <= 7.0.4 to remediate CVE-2026-42860.
• Implement egress filtering at the network level to block outbound connections from the Open edX server to 169.254.0.0/16 and RFC 1918 ranges as mentioned in the advisory.
• Deploy the Sigma rule “Detect Outbound Connection to AWS Metadata Endpoint” to monitor for connections to the AWS metadata service from the edx-enterprise server.