GitHub Advisoryadvisory · Go

GHSA-x86f-5xw2-fm2r Docker: `PUT /containers/{id}/archive` executes container binary on the host

HIGH Published 2026-05-18 Modified 2026-06-09 Official page ↗
Aliases
CVE-2026-41567
Ecosystem
Go
Packages
github.com/moby/moby/v2, github.com/docker/docker, github.com/moby/moby
Severity
High
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:N
Weaknesses
CWE-427
Reviewed
2026-05-18

Affected packages

• Go github.com/moby/moby/v2: < 2.0.0-beta.14 → fixed in 2.0.0-beta.14 • Go github.com/docker/docker: <= 28.5.2 (no fix yet) • Go github.com/moby/moby: <= 28.5.2 (no fix yet)

Description

Summary When a user uploads a compressed archive into a container, a malicious image can execute arbitrary code with daemon (host root) privileges. Details When handling `PUT /containers/{id}/archive` requests with compressed archives, the daemon decompresses them using external system binaries. Due to incorrect ordering of operations, these binaries are resolved from the container's filesystem rather than the host's. A container image that includes a trojanized decompression binary can achieve code execution as the daemon process whenever a compressed archive is uploaded to that container. The executed binary runs with the daemon's full privileges, including host root UID and unrestricted capabilities. Impact Arbitrary code execution as host root, crossing the container-to-host trust boundary. Conditions for exploitation • A user must run a container from a malicious image that contains a trojanized decompression binary. • The user must then upload a compressed archive (xz or gzip) into that container, either by piping a compressed archive via `docker cp -` or by calling the `PUT /containers/{id}/archive` API directly with compressed content. Not affected Standard `docker cp` usage is not affected, because the CLI sends uncompressed tar by default: ``` docker cp ./file.txt mycontainer:/file.txt ``` This can only be exploited when explicitly passing a xz or gzip-compressed archive to `docker cp` or the `PUT /containers/{id}/archive` API, for example: ``` cat archive.tar.xz | docker cp - mycontainer:/dir ``` Decompression formats using pure Go implementations (bzip2, zstd, and gzip when the container image does not contain an `unpigz` binary) are also not affected. Workarounds • Only run containers from trusted images. • Use authorization plugins to limit access to the `PUT /containers/{id}/archive` endpoint. • Avoid piping compressed archives into containers created from untrusted images.

Related

Alias · CVE (1)

  • CVE-2026-41567 Moby is an open source container framework. vulnerability

Weakness · CWE (1)

  • CWE-427 Uncontrolled Search Path Element weakness

References