Sagi Tzadik

Researcher fromWiz Research
#1724of 53,633
132.6Total CVSS
Vulnerabilities · 16
Medium
2
High
11
Critical
3
PT-2026-24344
9.0
2026-03-04
Github · Github Enterprise Server · CVE-2026-3854
**Name of the Vulnerable Software and Affected Versions** GitHub Enterprise Server versions prior to 3.14.25 GitHub Enterprise Server versions prior to 3.15.20 GitHub Enterprise Server versions prior to 3.16.16 GitHub Enterprise Server versions prior to 3.17.13 GitHub Enterprise Server versions prior to 3.18.8 GitHub Enterprise Server versions prior to 3.19.4 GitHub Enterprise Server versions prior to 3.20.0 **Description** An improper neutralization of special elements allows an authenticated attacker with push access to a repository to achieve remote code execution on the instance. During a `git push` operation, user-supplied push option values are not properly sanitized before being included in internal service headers. Specifically, the `babeld` proxy embeds these options into the `X-Stat` header without sanitizing semicolons (`;`), which serve as delimiter characters. This allows an attacker to inject and override internal metadata fields, such as `rails env`, `custom hooks dir`, and `repo pre receive hooks`, bypassing sandboxing and executing arbitrary commands via pre-receive hooks as the git service user. On GitHub Enterprise Server, this can lead to full server compromise, including access to all hosted repositories and internal secrets. On the cloud platform, the issue allowed remote code execution on shared storage nodes, potentially exposing millions of public and private repositories through cross-tenant exposure. Forensic investigations found no evidence of real-world exploitation prior to the patch. **Recommendations** Upgrade to version 3.14.25, 3.15.20, 3.16.16, 3.17.13, 3.18.8, 3.19.4, 3.20.0 or newer. As a temporary workaround, avoid running `git push` operations, especially those using the `-o` flag or custom push options, until the system is upgraded.