CVE-2026-8034

May 7, 2026, 10:16 p.m.

7.9
High

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.

Product(s) Impacted

Vendor Product Versions
Github
  • Github Enterprise Server
  • <3.21

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-436
Interpretation Conflict
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.

*CPE(s)

Affected systems and software identified for this CVE.

Type Vendor Product Version Update Edition Language Software Edition Target Software Target Hardware Other Information
a github github_enterprise_server <3.21 / / / / / / /

References

https://docs.github.com/en/[email protected]/admin/release-notes#3.16.18
https://docs.github.com/en/[email protected]/admin/release-notes#3.17.15
https://docs.github.com/en/[email protected]/admin/release-notes#3.18.9
https://docs.github.com/en/[email protected]/admin/release-notes#3.19.6
https://docs.github.com/en/[email protected]/admin/release-notes#3.20.2

Tags

CWE-436
[email protected]
2026-05-07
CVE-2026-8034

CVSS Score

7.9 / 10

CVSS Data - 4.0

  • Attack Vector: NETWORK
  • Attack Complexity: LOW
  • Attack Requirements: NONE
  • Privileges Required: NONE
  • User Interaction: NONE
  • Scope:
  • Confidentiality Impact: NONE
  • Integrity Impact: NONE
  • Availability Impact: NONE
  • Exploit Maturity: NOT_DEFINED

    • CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

    View Vector String

Timeline

Published: May 7, 2026, 10:16 p.m.
Last Modified: May 7, 2026, 10:16 p.m.

Status : Received

CVE has been recently published to the CVE List and has been received by the NVD.

More info

Source

[email protected]

*Disclaimer: Some vulnerabilities do not have an associated CPE. To enhance the data, we use AI to infer CPEs based on CVE details. This is an automated process and might not always be accurate.