UNIX Symbolic Link (Symlink) Following

runc is a CLI tool for spawning and running containers according to the OCI specification. runc 1.1.13 and earlier, as well as 1.2.0-rc2 and earlier, can be tricked into creating empty files or directories in arbitrary locations in the host filesystem by sharing a volume between two containers and exploiting a race with `os.MkdirAll`. While this could be used to create empty files, existing files would not be truncated. An attacker must have the ability to start containers using some kind of custom volume configuration. Containers using user namespaces are still affected, but the scope of places an attacker can create inodes can be significantly reduced. Sufficiently strict LSM policies (SELinux/Apparmor) can also in principle block this attack -- we suspect the industry standard SELinux policy may restrict this attack's scope but the exact scope of protection hasn't been analysed. This is exploitable using runc directly as well as through Docker and Kubernetes. The issue is fixed in runc v1.1.14 and v1.2.0-rc3. Some workarounds are available. Using user namespaces restricts this attack fairly significantly such that the attacker can only create inodes in directories that the remapped root user/group has write access to. Unless the root user is remapped to an actual user on the host (such as with rootless containers that don't use `/etc/sub[ug]id`), this in practice means that an attacker would only be able to create inodes in world-writable directories. A strict enough SELinux or AppArmor policy could in principle also restrict the scope if a specific label is applied to the runc runtime, though neither the extent to which the standard existing policies block this attack nor what exact policies are needed to sufficiently restrict this attack have been thoroughly tested.Show less

Dell PowerScale OneFS versions 8.2.2.x through 9.8.0.1 contains a UNIX symbolic link (symlink) following vulnerability. A local high privileged attacker could potentially exploit this vulnerability, leading to denial of service, information tampering.Show less

aiohttp is an asynchronous HTTP client/server framework for asyncio and Python. In versions on the 3.10 branch prior to version 3.10.2, static routes which contain files with compressed variants (`.gz` or `.br` extension) are vulnerable to path traversal outside the root directory if those variants are symbolic links. The server protects static routes from path traversal outside the root directory when `follow_symlinks=False` (default). It does this by resolving the requested URL to an absolute path and then checking that path relative to the root. However, these checks are not performed when looking for compressed variants in the `FileResponse` class, and symbolic links are then automatically followed when performing the `Path.stat()` and `Path.open()` to send the file. Version 3.10.2 contains a patch for the issue.Show less

Judge0 is an open-source online code execution system. The application uses the UNIX chown command on an untrusted file within the sandbox. An attacker can abuse this by creating a symbolic link (symlink) to a file outside the sandbox, allowing the attacker to run chown on arbitrary files outside of the sandbox. This vulnerability is not impactful on it's own, but it can be used to bypass the patch for CVE-2024-28185 and obtain a complete sandbox escape. This vulnerability is fixed in 1.13.1.Show less

Judge0 is an open-source online code execution system. The application does not account for symlinks placed inside the sandbox directory, which can be leveraged by an attacker to write to arbitrary files and gain code execution outside of the sandbox. When executing a submission, Judge0 writes a `run_script` to the sandbox directory. The security issue is that an attacker can create a symbolic link (symlink) at the path `run_script` before this code is executed, resulting in the `f.write` writing to an arbitrary file on the unsandboxed system. An attacker can leverage this vulnerability to overwrite scripts on the system and gain code execution outside of the sandbox. Show less

Dell PowerScale OneFS versions 9.4.0.x through 9.7.0.x contains an UNIX symbolic link (symlink) following vulnerability. A local high privileged attacker could potentially exploit this vulnerability, leading to denial of service, information tampering.Show less

Dell PowerScale OneFS versions 8.2.2.x through 9.7.0.x contains an UNIX symbolic link (symlink) following vulnerability. A local high privileged attacker could potentially exploit this vulnerability, leading to denial of service, information tampering.Show less

Insecure UNIX Symbolic Link (Symlink) Following in TeamViewer Remote Client prior Version 15.52 for macOS allows an attacker with unprivileged access, to potentially elevate privileges or conduct a denial-of-service-attack by overwriting the symlink.Show less

Dell Encryption, Dell Endpoint Security Suite Enterprise, and Dell Security Management Server version prior to 11.8.1 contain an Insecure Operation on Windows Junction Vulnerability during installation. A local malicious user could potentially exploit this vulnerability to create an arbitrary folder inside a restricted directory, leading to Privilege Escalation Show less

Plexis Archiver is a collection of Plexus components to create archives or extract archives to a directory with a unified `Archiver`/`UnArchiver` API. Prior to version 4.8.0, using AbstractUnArchiver for extracting an archive might lead to an arbitrary file creation and possibly remote code execution. When extracting an archive with an entry that already exists in the destination directory as a symbolic link whose target does not exist - the `resolveFile()` function will return the symlink's source instead of its target, which will pass the verification that ensures the file will not be extracted outside of the destination directory. Later `Files.newOutputStream()`, that follows symlinks by default, will actually write the entry's content to the symlink's target. Whoever uses plexus archiver to extract an untrusted archive is vulnerable to an arbitrary file creation and possibly remote code execution. Version 4.8.0 contains a patch for this issue.Show less

A symlink following vulnerability was found in Samba, where a user can create a symbolic link that will make 'smbd' escape the configured share path. This flaw allows a remote user with access to the exported part of the file system under a share via SMB1 unix extensions or NFS to create symlinks to files outside the 'smbd' configured share path and gain access to another restricted server's filesystem.Show less

A vulnerability, which was classified as problematic, was found in ReFirm Labs binwalk up to 2.3.2. Affected is an unknown function of the file src/binwalk/modules/extractor.py of the component Archive Extraction Handler. The manipulation leads to symlink following. It is possible to launch the attack remotely. Upgrading to version 2.3.3 is able to address this issue. The name of the patch is fa0c0bd59b8588814756942fe4cb5452e76c1dcd. It is recommended to upgrade the affected component. The identifier of this vulnerability is VDB-216876.Show less

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. All versions of Argo CD starting with v1.3.0 are vulnerable to a symlink following bug allowing a malicious user with repository write access to leak sensitive YAML files from Argo CD's repo-server. A malicious Argo CD user with write access for a repository which is (or may be) used in a Helm-type Application may commit a symlink which points to an out-of-bounds file. If the target file is a valid YAML file, the attacker can read the contents of that file. Sensitive files which could be leaked include manifest files from other Applications' source repositories (potentially decrypted files, if you are using a decryption plugin) or any YAML-formatted secrets which have been mounted as files on the repo-server. Patches for this vulnerability has been released in the following Argo CD versions: v2.4.1, v2.3.5, v2.2.10 and v2.1.16. If you are using a version >=v2.3.0 and do not have any Helm-type Applications you may disable the Helm config management tool as a workaround.Show less

Argo CD is a declarative, GitOps continuous delivery tool for Kubernetes. Argo CD starting with version 0.7.0 and prior to versions 2.1.15m 2.2.9, and 2.3.4 is vulnerable to a symlink following bug allowing a malicious user with repository write access to leak sensitive files from Argo CD's repo-server. A malicious Argo CD user with write access for a repository which is (or may be) used in a directory-type Application may commit a symlink which points to an out-of-bounds file. Sensitive files which could be leaked include manifest files from other Applications' source repositories (potentially decrypted files, if you are using a decryption plugin) or any JSON-formatted secrets which have been mounted as files on the repo-server. A patch for this vulnerability has been released in Argo CD versions 2.3.4, 2.2.9, and 2.1.15. Users of versions 2.3.0 or above who do not have any Jsonnet/directory-type Applications may disable the Jsonnet/directory config management tool as a workaround.Show less

A vulnerability in the Cisco IOS XE SD-WAN Software CLI could allow an authenticated, local attacker to overwrite arbitrary files on the local system. This vulnerability is due to improper access controls on files within the local file system. An attacker could exploit this vulnerability by placing a symbolic link in a specific location on the local file system. A successful exploit could allow the attacker to overwrite arbitrary files on an affected device.Show less