CVE-2026-8034
Analyzed
Analyzed - Analysis Complete
SSRF in GitHub Enterprise Server Notebook Viewer
Publication date: 2026-05-07
Last updated on: 2026-05-11
Assigner: GitHub, Inc. (Products Only)
Description
Description
A server-side request forgery (SSRF) vulnerability was identified in the GitHub Enterprise Server notebook viewer that allowed an attacker to access internal services by exploiting URL parser confusion between the validation layer and the HTTP request library. The hostname validation used a different URL parser than the request library, enabling a crafted URL to pass validation while directing the request to an unintended host. Exploitation required network access to the GitHub Enterprise Server instance. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.21 and was fixed in versions 3.16.18, 3.17.15, 3.18.9, 3.19.6, and 3.20.2. This vulnerability was reported via the GitHub Bug Bounty program.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| github | enterprise_server | From 3.20.0 (inc) to 3.20.2 (exc) |
| github | enterprise_server | to 3.16.18 (exc) |
| github | enterprise_server | From 3.17.0 (inc) to 3.17.15 (exc) |
| github | enterprise_server | From 3.18.0 (inc) to 3.18.9 (exc) |
| github | enterprise_server | From 3.19.0 (inc) to 3.19.6 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-918 | The web server receives a URL or similar request from an upstream component and retrieves the contents of this URL, but it does not sufficiently ensure that the request is being sent to the expected destination. |
| CWE-436 | Product A handles inputs or steps differently than Product B, which causes A to perform incorrect actions based on its perception of B's state. |
