Description

Open edX Platform enables the authoring and delivery of online learning at any scale. Prior to commit 00b7c3c, the endpoint accepts user-supplied files[].url, performs a server-side fetch using "requests.get(url, allow_redirects=True)". The fetched bytes are then returned inside a ZIP response. This enables SSRF with response exfiltration. Redirect-following is enabled, and there is no timeout in the vulnerable fetch path. This issue has been patched via commit 00b7c3c.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "6.8",
  "pubDate": "2026-09-02T17:17:46.290Z",
  "pubdate": "2026-09-02T17:17:46.290Z",
  "executiveSummary": "The Open edX Platform is vulnerable to a Server-Side Request Forgery (SSRF) flaw, which allows for the exfiltration of sensitive data from the internal network. This vulnerability exists because the application performs server-side file fetches from user-provided URLs without adequate validation or restriction.\nBy manipulating the files[].url parameter, an unauthenticated or authenticated attacker can force the server to issue HTTP GET requests to arbitrary destinations, including internal infrastructure, private cloud metadata services, or restricted internal network resources.\nBecause the server follows redirects by default and returns the fetched content within a ZIP response, the attacker can exfiltrate the contents of these internal resources directly to their client. This presents a high-risk scenario where an attacker can bypass firewalls, probe internal services, and gain access to sensitive information normally unreachable from the public internet. The vulnerability was addressed in commit 00b7c3c, which removed the unsafe fetch behavior.",
  "technicalDetails": "The root cause of this vulnerability is the improper implementation of a server-side resource fetching mechanism within the Open edX Platform. Specifically, the application utilized the requests.get(url, allow_redirects=True) function to process user-supplied input via the files[].url parameter. The application failed to implement a whitelist of allowed hostnames, protocols, or IP ranges, thereby permitting requests to arbitrary external and internal destinations.\nThe attack flow begins when an attacker crafts a malicious request containing a crafted URL in the files[].url parameter. Upon receiving this request, the Open edX server initiates a server-side HTTP GET request to the specified URL. Because the application explicitly enables allow_redirects=True, the server will follow subsequent HTTP 3xx responses. An attacker can leverage this behavior to redirect the server to internal endpoints or local loopback addresses (e.g., http://127.0.0.1 or http://169.254.169.254).\nThe lack of a defined request timeout further exacerbates the vulnerability, potentially allowing an attacker to conduct side-channel attacks or cause resource exhaustion by pointing the server to intentionally slow or hanging internal endpoints. The retrieved bytes from the destination are then wrapped into a ZIP response and delivered to the attacker's client. This provides an exfiltration vector, as the attacker effectively receives the response body of the targeted resource, including sensitive metadata, system configurations, or private API responses that reside within the protected network perimeter.\nThis vulnerability effectively turns the Open edX server into a proxy for the attacker, enabling them to bypass traditional network access controls (e.g., VPC security groups, internal firewalls). The affected component was corrected in commit 00b7c3c, which introduced necessary constraints on the URL fetching mechanism. Organizations utilizing versions prior to this commit are at risk of unauthorized internal network reconnaissance and data exfiltration."
}