Is CVE-2026-55421 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55421 being exploited in the wild.

How severe is CVE-2026-55421?

Medium severity, with a CVSS score of 6.8, published 2 September 2026.

Which products and versions are affected?

Open edX Platform Prior to commit 00b7c3c.

Is there a fix for CVE-2026-55421?

A patch was published on 2026-06-12: Fix merged via commits 00b7c3c and 241b914 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55421 attacked?

It is attacked over the network.

Am I affected by CVE-2026-55421?

Check whether you run Open edX Platform at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-55421: Open edX Platform SSRF in video download endpoint

CVE-2026-55421 · Severity: medium · CVSS 6.8 · Published 2026-09-02

Open edX is a platform that hosts online courses and training content. The video download feature in Studio (the course authoring tool) allows teachers to download videos associated with their course. An attacker with course authoring access could exploit this to retrieve sensitive data from internal servers or cloud metadata services by providing malicious video URLs, which the platform would fetch server-side and return to the attacker.

Technologies: Open edX Platform. Vendors: Open edX.

Quick answers

Is CVE-2026-55421 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55421 being exploited in the wild.
How severe is CVE-2026-55421?: Medium severity, with a CVSS score of 6.8, published 2 September 2026.
Which products and versions are affected?: Open edX Platform Prior to commit 00b7c3c.
Is there a fix for CVE-2026-55421?: A patch was published on 2026-06-12: Fix merged via commits 00b7c3c and 241b914 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55421 attacked?: It is attacked over the network.
Am I affected by CVE-2026-55421?: Check whether you run Open edX Platform at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability is a Server-Side Request Forgery (SSRF) in the PUT /api/contentstore/v1/videos/{course_id}/download endpoint. The endpoint accepts user-supplied URLs in a files[].url parameter, performs an unauthenticated server-side fetch using requests.get(url, allow_redirects=True), and returns the fetched bytes in a ZIP response. Because URLs are not validated against an allowlist before fetching, an authenticated user with studio read access can point them at internal services or cloud metadata endpoints and exfiltrate responses. The issue requires authentication and studio read access, but no URL validation or timeout exists in the vulnerable fetch path. The fix (commit 00b7c3c and 241b914) implements URL validation by restricting fetches to an allowlist of legitimate course video URLs before any HTTP request is made.

Affected products

Open edX Open edX Platform Prior to commit 00b7c3c

Timeline

2026-09-02: disclosed: CVE-2026-55421 published
2026-06-12: patched: Fix merged via commits 00b7c3c and 241b914

References

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