CVE-2026-46703

CRITICAL9.6

OCI layer symlink escape → arbitrary host write

Published: 5/21/2026Modified: 5/20/2026
Also known as:GHSA-f396-4rp4-7v2jRUSTSEC-2026-0148

Description

Affected versions of `boxlite` extract OCI image layer tarballs without fully containing path resolution to the extraction root. A crafted layer containing a symlink whose target is an absolute on-host path (e.g. `escape -> /tmp`) followed by a file entry that resolves through that symlink (e.g. `escape/<path>/pwned.txt`) caused the extractor to write the payload to the host filesystem outside the intended rootfs directory. The fix in v0.9.0 routes every destructive filesystem operation through a `SafeRoot` handle (`openat2(RESOLVE_IN_ROOT)` on Linux, lexical fallback elsewhere) so that no tar entry can resolve outside the extraction root, even with adversarial symlinks placed by earlier entries in the same layer. This is a container-escape during image extraction, exploitable by any user who pulls or loads a malicious OCI image — including via `SimpleBox(rootfs_path=...)` from an untrusted local layout.

Affected packages (6)

CVSS scores

SourceVersionSeverityVector
osvCVSS 3.1CRITICAL9.6CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H

References (7)