# Docker Sandboxes sandbox escape via poisoned Git config (CVE-2026-121614) · pwn.watch

> CVE-2026-121614 affects Docker Sandboxes 0.31.0 before 0.50.0. Host-side Git commands did not neutralize repository-controlled Git configuration. An attacker who can modify a host repository's Git config—for example through a direct-mode sandbox with the repo mounted read-write—can set core.fsmonitor or another setting that invokes an external program. A later clone-mode fetch, or from 0.39.0 an sbx kit push, can run that program on the host with the user's privileges, outside the microVM. Clone-mode's read-only host mount alone cannot poison the config. Fixed in Docker Sandboxes 0.50.0 (released Oct 26 2026; CVE published ~Nov 3). Vendor CVSS 4.0 is 7.1 (High). Upgrade to 0.50.0+; avoid read-write mounts of untrusted repos until patched.

Page: https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614 · generated 2026-11-04T14:14:08.250Z

## Status
- Severity: high · status: live · patch: patched
- Product: Docker Sandboxes (sbx)
- Started: 2026-10-26
- CVEs: CVE-2026-121614
- Affected: Docker Sandboxes 0.31.0 before 0.50.0
- Fixed in: 0.50.0; 0.51.0

## Follow this incident
- RSS (one item per update): https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614/feed.xml
- JSON Feed: https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614/feed.json
- Full data (timeline, sources, posts, agentBrief): https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614.json
- This file: https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614/llms.txt

## Updates (newest first)
- 2026-11-03: CVE-2026-121614 is published describing the Git-config sandbox escape in 0.31.0 before 0.50.0. (https://www.rapid7.com/db/vulnerabilities/cve-2026-121614/)
- 2026-10-26: Docker Sandboxes v0.50.0 ships: host Git commands no longer run programs configured by a sandbox through the workspace repository's .git directory. (https://github.com/docker/sbx-releases/releases/tag/v0.50.0)

## Fix brief
# Security brief: Docker Sandboxes sandbox escape via poisoned Git config (CVE-2026-121614)

Source: https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614 · status: live · severity: high · updated Nov 4, 2026, 11:40 UTC

## Patch status
**PATCHED: fixed releases exist. Upgrade to a fixed version.**

## What it is
CVE-2026-121614 affects Docker Sandboxes 0.31.0 before 0.50.0. Host-side Git commands did not neutralize repository-controlled Git configuration. An attacker who can modify a host repository's Git config—for example through a direct-mode sandbox with the repo mounted read-write—can set core.fsmonitor or another setting that invokes an external program. A later clone-mode fetch, or from 0.39.0 an sbx kit push, can run that program on the host with the user's privileges, outside the microVM. Clone-mode's read-only host mount alone cannot poison the config. Fixed in Docker Sandboxes 0.50.0 (released Oct 26 2026; CVE published ~Nov 3). Vendor CVSS 4.0 is 7.1 (High). Upgrade to 0.50.0+; avoid read-write mounts of untrusted repos until patched.

Severity detail: CVSS 4.0 7.1 sandbox escape to host code execution; needs write access to host Git config plus a later user-initiated Git operation

- Product: Docker Sandboxes (sbx)
- CVE / advisory ids: CVE-2026-121614

## Affected versions
- Docker Sandboxes 0.31.0 before 0.50.0

## Check whether you're affected
No generic command applies (the product is a hosted service, appliance or desktop app). Check the installed version in its admin UI / About screen and compare with the versions above.

## Fix
Upgrade to one of these fixed versions (or later on the same branch):
- 0.50.0
- 0.51.0

After upgrading, re-run the checks above and redeploy/restart the affected services.

## Specific notes
Upgrade Docker Sandboxes to 0.50.0 or later. Do not give direct-mode sandboxes read-write mounts on untrusted repositories until patched.

## Latest updates
- Nov 3, 2026: CVE-2026-121614 is published describing the Git-config sandbox escape in 0.31.0 before 0.50.0.
- Oct 26, 2026: Docker Sandboxes v0.50.0 ships: host Git commands no longer run programs configured by a sandbox through the workspace repository's .git directory.

## Advisories
- [Docker Sandboxes v0.50.0](https://github.com/docker/sbx-releases/releases/tag/v0.50.0) (Docker)
- [CVE-2026-121614](https://www.rapid7.com/db/vulnerabilities/cve-2026-121614/) (Rapid7 / CVE)

---
Machine-readable: https://pwn.watch/i/docker-sandboxes-git-config-escape-cve-2026-121614.json · all incidents: https://pwn.watch/incidents.json. Verify against the vendor advisory before changing production systems.