---
id: "CVE-2026-104608"
kind: "vulnerability"
aliases: ["CVE-2026-104608"]
title: "GitHub Enterprise Server: SSH-authenticated users can run commands via Git service"
severity: "high"
cvss: 7.7
epss: null
exploited: false
status: "open"
category: "vendor"
products: []
ecosystems: []
tags: ["git", "github-enterprise-server", "self-hosted", "ssh", "vendor"]
not_affected_if: ["managed-hosting", "no-untrusted-accounts", "ssh-disabled"]
published_at: "2026-11-03T23:17:24+00:00"
first_seen_at: "2026-11-03T23:45:12+00:00"
updated_at: "2026-11-03T23:45:29+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-104608", "first_seen_at": "2026-11-03T23:45:12+00:00"}]
---

# GitHub Enterprise Server: SSH-authenticated users can run commands via Git service

A use-after-free in the babeld Git service of GitHub Enterprise Server lets an attacker with an account and SSH access turn a memory bug into arbitrary command execution. The attacker runs commands as babeld and can read its environment secrets.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed GitHub Enterprise Server version in the site admin dashboard and compare it with the fixed versions below.
- Confirm whether SSH access is enabled for the instance and which users can authenticate over it.

## Fix

- Upgrade to `3.22.3` on the 3.22 line
- Upgrade to `3.21.8` on the 3.21 line
- Upgrade to `3.20.10` on the 3.20 line
- Upgrade to `3.19.14` on the 3.19 line

## Timeline

- 2026-11-03T23:45:12+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-104608

## From the sources

A remote code execution vulnerability was identified in GitHub Enterprise Server in the Git service (babeld). babeld held references into internal collections while calling into the SSH library, where a re-entrant callback could modify a collection and invalidate those references. An attacker with an account and SSH access to the instance could leverage this use-after-free into a controlled write and run arbitrary commands as babeld, including disclosure of its environment secrets. Exploitation required per-build memory offsets; failed attempts crashed babeld. This affected all releases prior to 3.23 and was fixed in 3.22.3, 3.21.8, 3.20.10, and 3.19.14. This vulnerability was reported via the GitHub Bug Bounty program.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_