Path Traversal in Chainguard Kaniko
CVE-2026-28406
kaniko is a tool to build container images from a Dockerfile, inside a container or Kubernetes cluster. Starting in version 1.25.4 and prior to version 1.25.10, kaniko unpacks build context archives using `filepath.Join(dest, cleanedName)` without enforcing that the final path stays within `dest`. A tar entry like `../outside.txt` escapes the extraction root and writes files outside the destination directory. In environments with registry authentication, this can be chained with docker credential helpers to achieve code execution within the executor process. Version 1.25.10 uses securejoin for path resolution in tar extraction.
Vulnerability class: Path Traversal (Directory Traversal)
EPSS: 0.006 (45.8th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L.
Affected products
- Chainguard Kaniko
- Chainguard-forks Kaniko — versions >= 1.25.4, < 1.25.10
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Patch, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (Patch, x_refsource_MISC)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-28406?
- CVE-2026-28406 is a high-severity vulnerability in Chainguard Kaniko, classified under Path Traversal. CVSS score: 8.2/10. Published 2026-02-27.
- How severe is CVE-2026-28406?
- High severity. CVSS v3 base score is 8.2 out of 10.