CVE Details

Release Date:2021-08-03


The npm package tar (aka node-tar) before versions 6.1.2, 5.0.7, 4.4.15, and 3.2.3 has an arbitrary File Creation/Overwrite vulnerability via insufficient symlink protection. node-tar aims to guarantee that any file whose location would be modified by a symbolic link is not extracted. This is, in part, achieved by ensuring that extracted directories are not symlinks. Additionally, in order to prevent unnecessary stat calls to determine whether a given path is a directory, paths are cached when directories are created. This logic was insufficient when extracting tar files that contained both a directory and a symlink with the same name as the directory. This order of operations resulted in the directory being created and added to the node-tar directory cache. When a directory is present in the directory cache, subsequent calls to mkdir for that directory are skipped. However, this is also where node-tar checks for symlinks occur. By first creating a directory, and then replacing that directory with a symlink, it was thus possible to bypass node-tar symlink checks on directories, essentially allowing an untrusted tar file to symlink into an arbitrary location and subsequently extracting arbitrary files into that location, thus allowing arbitrary file creation and overwrite. This issue was addressed in releases 3.2.3, 4.4.15, 5.0.7 and 6.1.2.

See more information about CVE-2021-32803 from MITRE CVE dictionary and NIST NVD

CVSS v3.0 metrics

NOTE: The following CVSS v3.0 metrics and score provided are preliminary and subject to review.

Base Score: 8.1 Base Metrics: AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
Access Vector: Network Attack Complexity: Low
Privileges Required: None User Interaction: Required
Scope: Unchanged Confidentiality Impact: None
Integrity Impact: High Availability Impact: High

Errata information

PlatformErrataRelease Date
Oracle Linux version 8 (nodejs)ELSA-2021-36232021-09-22
Oracle Linux version 8 (nodejs)ELSA-2021-36662021-09-27
Oracle Linux version 8 (nodejs-nodemon)ELSA-2021-36232021-09-22
Oracle Linux version 8 (nodejs-nodemon)ELSA-2021-36662021-09-27
Oracle Linux version 8 (nodejs-packaging)ELSA-2021-36232021-09-22
Oracle Linux version 8 (nodejs-packaging)ELSA-2021-36662021-09-27

This page is generated automatically and has not been checked for errors or omissions. For clarification or corrections please contact the Oracle Linux ULN team