Description
An Improper Neutralization of Input During Web Page Generation vulnerability was identified in GitHub Enterprise Server that allowed attacker controlled HTML to be rendered by the Filter component (search) across GitHub that could be used to exfiltrate sensitive information. An attacker would require permissions to create or modify the names of milestones, issues, pull requests, or similar entities that are rendered in the vulnerable filter/search components. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.20 and was fixed in versions 3.19.1, and 3.18.2, 3.17.8, 3.16.11, 3.15.15, and 3.14.20. This vulnerability was reported via the GitHub Bug Bounty program.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| GitHub | Enterprise Server | 3.14.0 – ≤ 3.14.19, 3.15.0 – ≤ 3.15.14, 3.16.0 – ≤ 3.16.10, 3.17.0 – ≤ 3.17.7, 3.18.0 – ≤ 3.18.1, 3.19 – ≤ 3.19.0 | — |
Advisories 1
- WID-SEC-2026-0023 Microsoft GitHub Enterprise Server: Schwachstelle ermöglicht Cross-Site Scripting BSI CERT-Bund (WID) · Jan 6, 2026
References
- https://docs.github.com/en/enterprise-server@3.14/admin/release-notes#3.14.20 release-notes
- https://docs.github.com/en/enterprise-server@3.15/admin/release-notes#3.15.15 release-notes
- https://docs.github.com/en/enterprise-server@3.16/admin/release-notes#3.16.11 release-notes
- https://docs.github.com/en/enterprise-server@3.17/admin/release-notes#3.17.8 release-notes
- https://docs.github.com/en/enterprise-server@3.18/admin/release-notes#3.18.2 release-notes
- https://docs.github.com/en/enterprise-server@3.19/admin/release-notes#3.19.1 release-notes