CVE-2021-32804
The npm package "tar" (aka node-tar) before versions 6.1.1, 5.0.6, 4.4.14, and 3.3.2 has a arbitrary File Creation/Overwrite vulnerability due to insufficient absolute path sanitization. node-tar aims to prevent extraction of absolute file paths by turning absolute paths into relative paths when the preservePaths flag is not set to true. This is achieved by stripping the absolute path root from any absolute file paths contained in a tar file. For example /home/user/.bashrc would turn into home/user/.bashrc. This logic was insufficient when file paths contained repeated path roots such as ////home/user/.bashrc. node-tar would only strip a single path root from such paths. When given an absolute file path with repeating path roots, the resulting path (e.g. ///home/user/.bashrc) would still resolve to an absolute path, thus allowing arbitrary file creation and overwrite. This issue was addressed in releases 3.2.2, 4.4.14, 5.0.6 and 6.1.1. Users may work around this vulnerability without upgrading by creating a custom onentry method which sanitizes the entry.path or a filter method which removes entries with absolute paths. See referenced GitHub Advisory for details. Be aware of CVE-2021-32803 which fixes a similar bug in later versions of tar.
| Software | From | Fixed in |
|---|---|---|
| tar_project / tar | 5.0.0 | 5.0.6 |
| tar_project / tar | - | 3.2.2 |
| tar_project / tar | 4.0.0 | 4.4.14 |
| tar_project / tar | 6.0.0 | 6.1.1 |
| oracle / graalvm | 20.3.3 | 20.3.3.x |
| oracle / graalvm | 21.2.0 | 21.2.0.x |
| siemens / sinec_infrastructure_network_services | - | 1.0.1.1 |
tar
|
- | 3.2.2 |
|
tar
|
4.0.0 | 4.4.14 |
|
tar
|
5.0.0 | 5.0.6 |
|
tar
|
6.0.0 | 6.1.1 |
- https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf
- https://github.com/npm/node-tar/commit/1f036ca23f64a547bdd6c79c1a44bc62e8115da4
- https://github.com/npm/node-tar/security/advisories/GHSA-3jfq-g458-7qm9
- https://www.npmjs.com/advisories/1770
- https://www.npmjs.com/package/tar
- https://www.oracle.com/security-alerts/cpuoct2021.html
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A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.
CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.
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