https://reddit.com/r/netsec/comments/1vlkth5/copyescape_containertohost_arbitrary_file_write/: CopyEscape: Container-to-host arbitrary file write via docker cp (CVE-2026-17106)

Q: Who is exposed to this issue?

The system running the Docker CLI is exposed when a user runs docker cp against a malicious container. The impact follows that CLI user's privileges, ranging from compromise of a developer account to root code execution.

Q: What does an attacker need to exploit it?

An attacker needs control of a container that a victim uses as the source for docker cp. The exploit uses a filesystem race during archive creation together with unsafe symlink handling during extraction to create or overwrite files on the CLI host.

Q: Which versions contain fixes?

Update Docker Engine/CLI to 29.7.2 or later, Docker Desktop to 4.86.0 or later, and Docker Sandboxes to 0.38.0 or later. Docker confirmed that sbx cp is also affected, so Sandbox users should update that component as well.

Published Aug 11, 2026

Updated

Affected Software

4 affected components

Docker Docker Engine<=29.7.2

Docker Docker CLI<=29.7.2

Docker Docker Desktop<=4.86.0

Docker Docker Sandboxes<=0.38.0

Frequently Asked Questions

Who is exposed to this issue?

The system running the Docker CLI is exposed when a user runs docker cp against a malicious container. The impact follows that CLI user's privileges, ranging from compromise of a developer account to root code execution.

What does an attacker need to exploit it?

An attacker needs control of a container that a victim uses as the source for docker cp. The exploit uses a filesystem race during archive creation together with unsafe symlink handling during extraction to create or overwrite files on the CLI host.

Which versions contain fixes?

Update Docker Engine/CLI to 29.7.2 or later, Docker Desktop to 4.86.0 or later, and Docker Sandboxes to 0.38.0 or later. Docker confirmed that sbx cp is also affected, so Sandbox users should update that component as well.