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

A TOCTOU and symlink race in svenstaro/miniserve 0.32.0 upload finalization (when uploads are enabled) can allow an attacker to overwrite arbitrary files outside the intended upload/document root in deployments where the attacker can create/replace filesystem entries in the upload destination directory (e.g., shared writable directory/volume).Show less

openCryptoki is a PKCS#11 library and provides tooling for Linux and AIX. Versions 2.3.2 and above are vulnerable to symlink-following when running in privileged contexts. A token-group user can redirect file operations to arbitrary filesystem targets by planting symlinks in group-writable token directories, resulting in privilege escalation or data exposure. Token and lock directories are 0770 (group-writable for token users), so any token-group member can plant files and symlinks inside them. When run as root, the base code handling token directory file access, as well as several openCryptoki tools used for administrative purposes, may reset ownership or permissions on existing files inside the token directories. An attacker with token-group membership can exploit the system when an administrator runs a PKCS#11 application or administrative tool that performs chown on files inside the token directory during normal maintenance. This issue is fixed in commit 5e6e4b4, but has not been included in a released version at the time of publication.Show less

Backstage is an open framework for building developer portals, and @backstage/cli-common provides config loading functionality used by the backend and command line interface of Backstage. Prior to version 0.1.17, the `resolveSafeChildPath` utility function in `@backstage/backend-plugin-api`, which is used to prevent path traversal attacks, failed to properly validate symlink chains and dangling symlinks. An attacker could bypass the path validation via symlink chains (creating `link1 → link2 → /outside` where intermediate symlinks eventually resolve outside the allowed directory) and dangling symlinks (creating symlinks pointing to non-existent paths outside the base directory, which would later be created during file operations). This function is used by Scaffolder actions and other backend components to ensure file operations stay within designated directories. This vulnerability is fixed in `@backstage/backend-plugin-api` version 0.1.17. Users should upgrade to this version or later. Some workarounds are available. Run Backstage in a containerized environment with limited filesystem access and/or restrict template creation to trusted users.Show less

Backstage is an open framework for building developer portals. Multiple Scaffolder actions and archive extraction utilities were vulnerable to symlink-based path traversal attacks. An attacker with access to create and execute Scaffolder templates could exploit symlinks to read arbitrary files via the `debug:log` action by creating a symlink pointing to sensitive files (e.g., `/etc/passwd`, configuration files, secrets); delete arbitrary files via the `fs:delete` action by creating symlinks pointing outside the workspace, and write files outside the workspace via archive extraction (tar/zip) containing malicious symlinks. This affects any Backstage deployment where users can create or execute Scaffolder templates. This vulnerability is fixed in `@backstage/backend-defaults` versions 0.12.2, 0.13.2, 0.14.1, and 0.15.0; `@backstage/plugin-scaffolder-backend` versions 2.2.2, 3.0.2, and 3.1.1; and `@backstage/plugin-scaffolder-node` versions 0.11.2 and 0.12.3. Users should upgrade to these versions or later. Some workarounds are available. Follow the recommendation in the Backstage Threat Model to limit access to creating and updating templates, restrict who can create and execute Scaffolder templates using the permissions framework, audit existing templates for symlink usage, and/or run Backstage in a containerized environment with limited filesystem access.Show less

virtualenv is a tool for creating isolated virtual python environments. Prior to version 20.36.1, TOCTOU (Time-of-Check-Time-of-Use) vulnerabilities in virtualenv allow local attackers to perform symlink-based attacks on directory creation operations. An attacker with local access can exploit a race condition between directory existence checks and creation to redirect virtualenv's app_data and lock file operations to attacker-controlled locations. This issue has been patched in version 20.36.1.Show less

filelock is a platform-independent file lock for Python. Prior to version 3.20.3, a TOCTOU race condition vulnerability exists in the SoftFileLock implementation of the filelock package. An attacker with local filesystem access and permission to create symlinks can exploit a race condition between the permission validation and file creation to cause lock operations to fail or behave unexpectedly. The vulnerability occurs in the _acquire() method between raise_on_not_writable_file() (permission check) and os.open() (file creation). During this race window, an attacker can create a symlink at the lock file path, potentially causing the lock to operate on an unintended target file or leading to denial of service. This issue has been patched in version 3.20.3.Show less

A path traversal vulnerability has been reported to affect several product versions. If a local attacker gains a user account, they can then exploit the vulnerability to read the contents of unexpected files or system data. We have already fixed the vulnerability in the following versions: Qfinder Pro Mac 7.13.0 and later Qsync for Mac 5.1.5 and later QVPN Device Client for Mac 2.2.8 and laterShow less

MSP360 Free Backup Link Following Local Privilege Escalation Vulnerability. This vulnerability allows local attackers to escalate privileges on affected installations of MSP360 Free Backup. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. User interaction on the part of an administrator is needed additionally. The specific flaw exists within the restore functionality. By creating a junction, an attacker can abuse the service to create arbitrary files. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-27245.Show less

Zillya Total Security 3.0.2367.0 contains a privilege escalation vulnerability that allows low-privileged users to copy files to unauthorized system locations using the quarantine module. Attackers can leverage symbolic link techniques to restore quarantined files to restricted directories, potentially enabling system-level access through techniques like DLL hijacking.Show less

filelock is a platform-independent file lock for Python. In versions prior to 3.20.1, a Time-of-Check-Time-of-Use (TOCTOU) race condition allows local attackers to corrupt or truncate arbitrary user files through symlink attacks. The vulnerability exists in both Unix and Windows lock file creation where filelock checks if a file exists before opening it with O_TRUNC. An attacker can create a symlink pointing to a victim file in the time gap between the check and open, causing os.open() to follow the symlink and truncate the target file. All users of filelock on Unix, Linux, macOS, and Windows systems are impacted. The vulnerability cascades to dependent libraries. The attack requires local filesystem access and ability to create symlinks (standard user permissions on Unix; Developer Mode on Windows 10+). Exploitation succeeds within 1-3 attempts when lock file paths are predictable. The issue is fixed in version 3.20.1. If immediate upgrade is not possible, use SoftFileLock instead of UnixFileLock/WindowsFileLock (note: different locking semantics, may not be suitable for all use cases); ensure lock file directories have restrictive permissions (chmod 0700) to prevent untrusted users from creating symlinks; and/or monitor lock file directories for suspicious symlinks before running trusted applications. These workarounds provide only partial mitigation. The race condition remains exploitable. Upgrading to version 3.20.1 is strongly recommended.Show less

A vulnerability has been found in Ugreen DH2100+ up to 5.3.0. This affects an unknown function of the component USB Handler. Such manipulation leads to symlink following. The attack can be executed directly on the physical device. The exploit has been disclosed to the public and may be used. It is suggested to upgrade the affected component.Show less

A local privilege escalation vulnerability in Bitdefender Total Security versions prior to 27.0.47.241 allows low-privileged attackers to elevate privileges. The issue arises from bdservicehost.exe deleting files from a user-writable directory (C:\ProgramData\Atc\Feedback) without proper symbolic link validation, enabling arbitrary file deletion. This issue is chained with a file copy operation during network events and a filter driver bypass via DLL injection to achieve arbitrary file copy and code execution as elevated user.Show less

Argo Workflows is an open source container-native workflow engine for orchestrating parallel jobs on Kubernetes. Versions 3.6.13 and below and versions 3.7.0 through 3.7.4, contain unsafe untar code that handles symbolic links in archives. Concretely, the computation of a link's target and the subsequent check are flawed. An attacker can overwrite the file /var/run/argo/argoexec with a script of their choice, which would be executed at the pod's start. The patch deployed against CVE-2025-62156 is ineffective against malicious archives containing symbolic links. This issue is fixed in versions 3.6.14 and 3.7.5.Show less

Dell Encryption, versions prior to 11.12.1, contain an Improper Link Resolution Before File Access ('Link Following') vulnerability. A local malicious user could potentially exploit this vulnerability, leading to Elevation of privileges.Show less

Dell Encryption, versions prior to 11.12.1, contain an Improper Link Resolution Before File Access ('Link Following') vulnerability. A low privileged attacker with local access could potentially exploit this vulnerability, leading to Information tampering.Show less