CWE-59

A symbolic link issue was found in rpm. It occurs when rpm sets the desired permissions and credentials after installing a file. A local unprivileged user could use this flaw to exchange the original file with a symbolic link to a security-critical file and escalate their privileges on the system. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

It was found that the fix for CVE-2017-7500 and CVE-2017-7501 was incomplete: the check was only implemented for the parent directory of the file to be created. A local unprivileged user who owns another ancestor directory could potentially use this flaw to gain root privileges. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

The Zoom Client for Meetings for Windows in all versions before version 5.3.2 writes log files to a user writable directory as a privileged user during the installation or update of the client. This could allow for potential privilege escalation if a link was created between the user writable directory used and a non-user writable directory.

Western Digital My Cloud OS 5 devices before 5.10.122 mishandle Symbolic Link Following on SMB and AFP shares. This can lead to code execution and information disclosure (by reading local files).

bblfshd is an open source self-hosted server for source code parsing. In bblfshd before commit 4265465b9b6fb5663c30ee43806126012066aad4 there is a “zipslip” vulnerability. The unsafe handling of symbolic links in an unpacking routine may enable attackers to read and/or write to arbitrary locations outside the designated target folder. This issue may lead to arbitrary file write (with same permissions as the program running the unpack operation) if the attacker can control the archive file. Additionally, if the attacker has read access to the unpacked files, he may be able to read arbitrary system files the parent process has permissions to read. For more details including a PoC see the referenced GHSL-2020-258.

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.