Description
The tar extraction routines in moby/go-archive (Unpack, UnpackLayer, Untar/UntarUncompressed, and the ApplyLayer helpers) do not confine filesystem operations to the destination directory. The extractor decides where each archive entry lands using lexical string checks and then performs the filesystem operation on a path that is resolved by the OS, so links introduced by the archive can be followed out of the destination directory. An attacker who controls the contents of an archive can create or overwrite files at arbitrary paths writable by the extracting process.
References8
- docs.docker.com/desktop/release-notes/#4860
- docs.docker.com/engine/release-notes/29/#2970
- github.com/docker/cli/releases/tag/v29.7.0
- github.com/docker/compose/releases/tag/v5.4.0
- github.com/docker/sbx-releases/releases/tag/v0.38.0
- github.com/moby/go-archive/releases/tag/v0.3.0
- github.com/moby/go-archive/security/advisories/GHSA-hfg8-hc9c-6…
- github.com/masasron/CopyEscape-CVE-2026-17106
Metrics
- CVSS 4.0
-
7.1
HIGH
Score source: CNA
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 39 · as of 11 November 2026
- CWE
- CWE-59
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.