Improper Link Resolution Before File Access ('Link Following')

A security vulnerability that can lead to local privilege escalation has been found in ’guix-daemon’. It affects multi-user setups in which ’guix-daemon’ runs locally. The attack consists in having an unprivileged user spawn a build process, for instance with `guix build`, that makes its build directory world-writable. The user then creates a hardlink to a root-owned file such as /etc/shadow in that build directory. If the user passed the --keep-failed option and the build eventually fails, the daemon changes ownership of the whole build tree, including the hardlink, to the user. At that point, the user has write access to the target file. Versions after and including v0.11.0-3298-g2608e40988, and versions prior to v1.2.0-75109-g94f0312546 are vulnerable.Show less

An issue was discovered in Forescout CounterACT before 8.1.4. A local privilege escalation vulnerability is present in the logging function. SecureConnector runs with administrative privileges and writes logs entries to a file in %PROGRAMDATA%\ForeScout SecureConnector\ that has full permissions for the Everyone group. Using a symbolic link allows an attacker to point the log file to a privileged location such as %WINDIR%\System32. The resulting log file adopts the file permissions of the source of the symbolic link (in this case, the Everyone group). The log file in System32 can be replaced and renamed with a malicious DLL for DLL hijacking.Show less

VestaCP through 0.9.8-24 allows attackers to gain privileges by creating symlinks to files for which they lack permissions. After reading the RKEY value from user.conf under the /usr/local/vesta/data/users/admin directory, the admin password can be changed via a /reset/?action=confirm&user=admin&code= URI. This occurs because chmod is used unsafely.Show less

fr-archive-libarchive.c in GNOME file-roller through 3.38.0, as used by GNOME Shell and other software, allows Directory Traversal during extraction because it lacks a check of whether a file's parent is a symlink in certain complex situations. NOTE: this issue exists because of an incomplete fix for CVE-2020-11736.Show less

In Eclipse Jetty 9.4.32 to 9.4.38, 10.0.0.beta2 to 10.0.1, and 11.0.0.beta2 to 11.0.1, if a user uses a webapps directory that is a symlink, the contents of the webapps directory is deployed as a static webapp, inadvertently serving the webapps themselves and anything else that might be in that directory.Show less

This vulnerability allows local attackers to delete arbitrary directories on affected installations of Avast Premium Security 20.8.2429 (Build 20.8.5653.561). An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. The specific flaw exists within the AvastSvc.exe module. By creating a directory junction, an attacker can abuse the service to delete a directory. An attacker can leverage this vulnerability to create a denial-of-service condition on the system. Was ZDI-CAN-12082.Show less

There is an open race window when writing output in the following utilities in GNU binutils version 2.35 and earlier:ar, objcopy, strip, ranlib. When these utilities are run as a privileged user (presumably as part of a script updating binaries across different users), an unprivileged user can trick these utilities into getting ownership of arbitrary files through a symlink.Show less

Privilege Escalation vulnerability in McAfee Data Loss Prevention (DLP) for Windows prior to 11.6.100 allows a local, low privileged, attacker through the use of junctions to cause the product to load DLLs of the attacker's choosing. This requires the creation and removal of junctions by the attacker along with sending a specific IOTL command at the correct time.Show less

autoar-extractor.c in GNOME gnome-autoar before 0.3.1, as used by GNOME Shell, Nautilus, and other software, allows Directory Traversal during extraction because it lacks a check of whether a file's parent is a symlink in certain complex situations. NOTE: this issue exists because of an incomplete fix for CVE-2020-36241.Show less

An issue was discovered in GNOME GLib before 2.66.8. When g_file_replace() is used with G_FILE_CREATE_REPLACE_DESTINATION to replace a path that is a dangling symlink, it incorrectly also creates the target of the symlink as an empty file, which could conceivably have security relevance if the symlink is attacker-controlled. (If the path is a symlink to a file that already exists, then the contents of that file correctly remain unchanged.)Show less

<p>An elevation of privilege vulnerability exists in Microsoft Windows when Folder redirection has been enabled via Group Policy. When folder redirection file server is co-located with Terminal server, an attacker who successfully exploited the vulnerability would be able to begin redirecting another user's personal data to a created folder.</p> <p>To exploit the vulnerability, an attacker can create a new folder under the Folder Redirection root path and create a junction on a newly created User folder. When the new user logs in, Folder Redirection would start redirecting to the folder and copying personal data.</p> <p>This elevation of privilege vulnerability can only be addressed by reconfiguring Folder Redirection with Offline files and restricting permissions, and NOT via a security update for affected Windows Servers. See the <strong>FAQ</strong> section of this CVE for configuration guidance.</p>Show less

A vulnerability exists in IBM SPSS Modeler Subscription Installer that allows a user with create symbolic link permission to write arbitrary file in another protected path during product installation. IBM X-Force ID: 187727.Show less