Synopsis
The remote Debian host is missing one or more security-related updates.
Description
The remote Debian 10 host has a package installed that is affected by multiple vulnerabilities as referenced in the dla-3237 advisory.
- The npm package tar (aka node-tar) before versions 4.4.16, 5.0.8, and 6.1.7 has an arbitrary file creation/overwrite and arbitrary code execution vulnerability. 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, where the symlink and directory names in the archive entry used backslashes as a path separator on posix systems. The cache checking logic used both `\` and `/` characters as path separators, however `\` is a valid filename character on posix systems. 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. Additionally, a similar confusion could arise on case-insensitive filesystems. If a tar archive contained a directory at `FOO`, followed by a symbolic link named `foo`, then on case-insensitive file systems, the creation of the symbolic link would remove the directory from the filesystem, but _not_ from the internal directory cache, as it would not be treated as a cache hit. A subsequent file entry within the `FOO` directory would then be placed in the target of the symbolic link, thinking that the directory had already been created. These issues were addressed in releases 4.4.16, 5.0.8 and 6.1.7. The v3 branch of node-tar has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of node-tar.
If this is not possible, a workaround is available in the referenced GHSA-9r2w-394v-53qc. (CVE-2021-37701)
- The npm package tar (aka node-tar) before versions 4.4.18, 5.0.10, and 6.1.9 has an arbitrary file creation/overwrite and arbitrary code execution vulnerability. 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 names containing unicode values that normalized to the same value. Additionally, on Windows systems, long path portions would resolve to the same file system entities as their 8.3 short path counterparts. A specially crafted tar archive could thus include a directory with one form of the path, followed by a symbolic link with a different string that resolves to the same file system entity, followed by a file using the first form. By first creating a directory, and then replacing that directory with a symlink that had a different apparent name that resolved to the same entry in the filesystem, 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. These issues were addressed in releases 4.4.18, 5.0.10 and 6.1.9.
The v3 branch of node-tar has been deprecated and did not receive patches for these issues. If you are still using a v3 release we recommend you update to a more recent version of node-tar. If this is not possible, a workaround is available in the referenced GHSA-qq89-hq3f-393p. (CVE-2021-37712)
Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.
Solution
Upgrade the node-tar packages.
For Debian 10 buster, these problems have been fixed in version 4.4.6+ds1-3+deb10u2.
Plugin Details
File Name: debian_DLA-3237.nasl
Agent: unix
Supported Sensors: Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus
Risk Information
Vector: CVSS2#AV:L/AC:M/Au:N/C:P/I:P/A:P
Vector: CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H
Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C
Vulnerability Information
CPE: cpe:/o:debian:debian_linux:10.0, p-cpe:/a:debian:debian_linux:node-tar
Required KB Items: Host/local_checks_enabled, Host/Debian/release, Host/Debian/dpkg-l
Exploit Ease: No known exploits are available
Patch Publication Date: 12/12/2022
Vulnerability Publication Date: 8/31/2021