CVE-2021-32803

Aliases:GHSA-r628-mhmh-qjhw
Advisory lineage Upstream: 0 Downstream: 22
Modified
Published: 03 Aug 2021, 19:05
Last modified:03 Aug 2024, 23:33

Vulnerability Summary

Overall Risk (default)
medium
33/100
CVSS Score
8.2 HIGH
v3.1 (cve.org)
EPSS Score
0.12% LOW
0% probability -0.04%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

03 Aug 2021, 19:05
Published
Vulnerability first disclosed
03 Aug 2024, 23:33
Last Modified
Vulnerability information updated

Description

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.

CVSS Metrics

  • v3.1•HIGH•Score: 8.2CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N
  • v3.1•HIGH•Score: 8.1CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H
  • v2.0•MEDIUM•Score: 5.8AV:N/AC:M/Au:N/C:N/I:P/A:P

EPSS Trends

Current EPSS score: 0.12%• Percentile: 31%

Techniques & Countermeasures

  • CWE-59•Improper Link Resolution Before File Access ('Link Following')

    The product attempts to access a file based on the filename, but it does not properly prevent that filename from identifying a link or shortcut that resolves to an unintended resource.

  • CWE-22•Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

    The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.

Affected Systems

  • npm•node-tar

    < 3.2.3 | ≥ 4.0.0, < 4.4.15 | ≥ 5.0.0, < 5.0.7 | ≥ 6.0.0, < 6.1.2

  • Npm•tar

    ≥ 3.0.0, < 3.2.3 | ≥ 4.0.0, < 4.4.15 | ≥ 5.0.0, < 5.0.7 | ≥ 6.0.0, < 6.1.2

  • oracle•graalvm

    20.3.3 | 21.2.0

  • siemens•sinec_infrastructure_network_services

    < 1.0.1.1

  • tar_project•tar

    < 3.2.3 | ≥ 4.0.0, < 4.4.15 | ≥ 5.0.0, < 5.0.7 | ≥ 6.0.0, < 6.1.2

References (12)