UNIX Symbolic Link (Symlink) Following

Zed, a code editor, has an extension installer allows tar/gzip downloads. Prior to version 0.224.4, the tar extractor (`async_tar::Archive::unpack`) creates symlinks from the archive without validation, and the path guard (`writeable_path_from_extension`) only performs lexical prefix checks without resolving symlinks. An attacker can ship a tar that first creates a symlink inside the extension workdir pointing outside (e.g., `escape -> /`), then writes files through the symlink, causing writes to arbitrary host paths. This escapes the extension sandbox and enables code execution. Version 0.224.4 patches the issue.Show less

OpenClaw is a personal AI assistant. In versions 2026.2.17 and below, skills/skill-creator/scripts/package_skill.py (a local helper script used when authors package skills) previously followed symlinks while building .skill archives. If an author runs this script on a crafted local skill directory containing symlinks to files outside the skill root, the resulting archive can include unintended file contents. If exploited, this vulnerability can lead to potential unintentional disclosure of local files from the packaging machine into a generated .skill artifact, but requires local execution of the packaging script on attacker-controlled skill contents. This issue has been fixed in version 2026.2.18.Show less

Claude Code is an agentic coding tool. Prior to version 2.1.7, Claude Code failed to strictly enforce deny rules configured in settings.json when accessing files through symbolic links. If a user explicitly denied Claude Code access to a file (such as /etc/passwd) and Claude Code had access to a symbolic link pointing to that file, it was possible for Claude Code to read the restricted file through the symlink without triggering deny rule enforcement. This issue has been patched in version 2.1.7.Show less

A UNIX symbolic link following issue in the jailer component in Firecracker version v1.13.1 and earlier and 1.14.0 on Linux may allow a local host user with write access to the pre-created jailer directories to overwrite arbitrary host files via a symlink attack during the initialization copy at jailer startup, if the jailer is executed with root privileges. To mitigate this issue, users should upgrade to version v1.13.2 or 1.14.1 or above.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

Copier is a library and CLI app for rendering project templates. Prior to version 9.11.2, Copier suggests that it's safe to generate a project from a safe template, i.e. one that doesn't use unsafe features like custom Jinja extensions which would require passing the `--UNSAFE,--trust` flag. As it turns out, a safe template can currently write to arbitrary directories outside the destination path by using directory a symlink along with `_preserve_symlinks: true` and a generated directory structure whose rendered path is inside the symlinked directory. This way, a malicious template author can create a template that overwrites arbitrary files (according to the user's write permissions), e.g., to cause havoc. Version 9.11.2 patches the issue.Show less

Copier is a library and CLI app for rendering project templates. Prior to version 9.11.2, Copier suggests that it's safe to generate a project from a safe template, i.e. one that doesn't use unsafe features like custom Jinja extensions which would require passing the `--UNSAFE,--trust` flag. As it turns out, a safe template can currently include arbitrary files/directories outside the local template clone location by using symlinks along with `_preserve_symlinks: false` (which is Copier's default setting). Version 9.11.2 patches the issue.Show less

Forgejo before 13.0.2 allows attackers to write to unintended files, and possibly obtain server shell access, because of mishandling of out-of-repository symlink destinations for template repositories. This is also fixed for 11 LTS in 11.0.7 and later.Show less

NVIDIA Resiliency Extension for Linux contains a vulnerability in log aggregation, where an attacker could cause predictable log-file names. A successful exploit of this vulnerability may lead to escalation of privileges, code execution, denial of service, information disclosure, and data tampering.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

Static Web Server (SWS) is a production-ready web server suitable for static web files or assets. Versions 2.40.0 and below contain symbolic links (symlinks) which can be used to access files or directories outside the intended web root folder. SWS generally does not prevent symlinks from escaping the web server’s root directory. Therefore, if a malicious actor gains access to the web server’s root directory, they could create symlinks to access other files outside the designated web root folder either by URL or via the directory listing. This issue is fixed in version 2.40.1.Show less

WebPros Plesk before 18.0.73.5 and 18.0.74 before 18.0.74.2 on Linux allows remote authenticated users to execute arbitrary code as root via domain creation. The attacker needs "Create and manage sites" with "Domains management" and "Subdomains management."Show less

Apptainer is an open source container platform. In Apptainer versions less than 1.4.5, a container can disable two of the forms of the little used --security option, in particular the forms --security=apparmor:<profile> and --security=selinux:<label> which otherwise put restrictions on operations that containers can do. The --security option has always been mentioned in Apptainer documentation as being a feature for the root user, although these forms do also work for unprivileged users on systems where the corresponding feature is enabled. Apparmor is enabled by default on Debian-based distributions and SElinux is enabled by default on RHEL-based distributions, but on SUSE it depends on the distribution version. This vulnerability is fixed in 1.4.5.Show less

SingularityCE and SingularityPRO are open source container platforms. Prior to SingularityCE 4.3.5 and SingularityPRO 4.1.11 and 4.3.5, if a user relies on LSM restrictions to prevent malicious operations then, under certain circumstances, an attacker can redirect the LSM label write operation so that it is ineffective. The attacker must cause the user to run a malicious container image that redirects the mount of /proc to the destination of a shared mount, either known to be configured on the target system, or that will be specified by the user when running the container. The attacker must also control the content of the shared mount, for example through another malicious container which also binds it, or as a user with relevant permissions on the host system it is bound from. This vulnerability is fixed in SingularityCE 4.3.5 and SingularityPRO 4.1.11 and 4.3.5.Show less

Open OnDemand is an open-source HPC portal. Prior to versions 4.0.8 and 3.1.16, users can craft a "Time of Check to Time of Use" (TOCTOU) attack when downloading zip files to access files outside of the OOD_ALLOWLIST. This vulnerability impacts sites that use the file browser allowlists in all current versions of OOD. However, files accessed are still protected by the UNIX permissions. Open OnDemand versions 4.0.8 and 3.1.16 have been patched for this vulnerability.Show less

runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7, 1.3.2 and 1.4.0-rc.2, an attacker can trick runc into misdirecting writes to /proc to other procfs files through the use of a racing container with shared mounts (we have also verified this attack is possible to exploit using a standard Dockerfile with docker buildx build as that also permits triggering parallel execution of containers with custom shared mounts configured). This redirect could be through symbolic links in a tmpfs or theoretically other methods such as regular bind-mounts. While similar, the mitigation applied for the related CVE, CVE-2019-19921, was fairly limited and effectively only caused runc to verify that when LSM labels are written they are actually procfs files. This issue is fixed in versions 1.2.8, 1.3.3, and 1.4.0-rc.3.Show less

runc is a CLI tool for spawning and running containers according to the OCI specification. Versions 1.0.0-rc3 through 1.2.7, 1.3.0-rc.1 through 1.3.2, and 1.4.0-rc.1 through 1.4.0-rc.2, due to insufficient checks when bind-mounting `/dev/pts/$n` to `/dev/console` inside the container, an attacker can trick runc into bind-mounting paths which would normally be made read-only or be masked onto a path that the attacker can write to. This attack is very similar in concept and application to CVE-2025-31133, except that it attacks a similar vulnerability in a different target (namely, the bind-mount of `/dev/pts/$n` to `/dev/console` as configured for all containers that allocate a console). This happens after `pivot_root(2)`, so this cannot be used to write to host files directly -- however, as with CVE-2025-31133, this can load to denial of service of the host or a container breakout by providing the attacker with a writable copy of `/proc/sysrq-trigger` or `/proc/sys/kernel/core_pattern` (respectively). This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.Show less

runc is a CLI tool for spawning and running containers according to the OCI specification. In versions 1.2.7 and below, 1.3.0-rc.1 through 1.3.1, 1.4.0-rc.1 and 1.4.0-rc.2 files, runc would not perform sufficient verification that the source of the bind-mount (i.e., the container's /dev/null) was actually a real /dev/null inode when using the container's /dev/null to mask. This exposes two methods of attack: an arbitrary mount gadget, leading to host information disclosure, host denial of service, container escape, or a bypassing of maskedPaths. This issue is fixed in versions 1.2.8, 1.3.3 and 1.4.0-rc.3.Show less

Youki is a container runtime written in Rust. In versions 0.5.6 and below, youki’s apparmor handling performs insufficiently strict write-target validation, and when combined with path substitution during pathname resolution, can allow writes to unintended procfs locations. While resolving a path component-by-component, a shared-mount race can substitute intermediate components and redirect the final target. This issue is fixed in version 0.5.7.Show less