An improper access control vulnerability was identified in GitHub Enterprise Server that allowed users with access to any repository to retrieve limited code content from another repository by creating a diff between the repositories. To exploit this vulnerability, an attacker needed to know the name of a private repository along with its branches, tags, or commit SHAs that they could use to trigger compare/diff functionality and retrieve limited code without proper authorization. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.18, and was fixed in versions 3.14.17, 3.15.12, 3.16.8 and 3.17.5. This vulnerability was reported via the GitHub Bug Bounty program.
Conclusion & alert: CVE-2025-8447 is rated Low Risk (35.2/100): CVSS High severity, with low exploitation likelihood (EPSS 0.28%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-06-15 | 0.04% | 0.28% | +0.24% |
| 2 | 2025-08-26 | — | 0.04% | — |
Full EPSS history (2 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 7.0 | 4.0 | HIGH |
|
— | — | [email protected] |
| 3.1 | 3.1 | LOW |
|
1.6 | 1.4 | [email protected] |
| Vendor | Product | Version | Raw CPE |
|---|---|---|---|
| github | enterprise_server | < 3.14.17 | cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* |
| github | enterprise_server | >= 3.15.0, < 3.15.12 | cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* |
| github | enterprise_server | >= 3.16.0, < 3.16.8 | cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* |
| github | enterprise_server | >= 3.17.0, < 3.17.5 | cpe:2.3:a:github:enterprise_server:*:*:*:*:*:*:*:* |