CVE-2026-8034 (GCVE-0-2026-8034)
Vulnerability from cvelistv5
Published
2026-05-07 21:18
Modified
2026-05-08 13:03
Severity ?
VLAI Severity ?
EPSS score ?
Summary
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.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| GitHub | Enterprise Server |
Version: 3.16.0 ≤ 3.16.17 Version: 3.17.0 ≤ 3.17.14 Version: 3.18.0 ≤ 3.18.8 Version: 3.19.0 ≤ 3.19.5 Version: 3.20.0 ≤ 3.20.1 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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