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

Incus before 6.0.7, 6.1.0 before 7.0.2, and 7.1.0 before 7.5.0 contains an arbitrary file write vulnerability in sftpRecursivePullFile that allows a malicious incus-agent to escape the target directory during incus file pull -r. Attackers with root in a virtual machine can return duplicate entries reported first as symlinks then as files or directories, writing attacker-controlled files such as /etc/shadow on the operator's host.Show less

Incus before 6.0.7, 6.1.0 before 7.0.2, and 7.1.0 before 7.5.0 contains an arbitrary file write vulnerability that allows malicious migration sources to write host files by planting symlinks in transferred volumes. Attackers can craft rsync or btrfs receive streams with a symlink such as rootfs pointing to the host root, writing files as root for full host compromise.Show less

JetBackup plugin for WordPress before 3.1.24.10 contains a symlink-based arbitrary file write vulnerability that allows an authenticated WordPress administrator to write attacker-controlled file contents outside the intended restore destination during backup import and restore. Attackers can craft a backup archive containing a symbolic link that archive extraction follows without validating targets or enforcing destination containment, potentially leading to server-side code execution depending on the writable destination and server configuration.Show less

Goploy 1.18.0 before 1.18.1 contains a link following vulnerability in the /deploy/fileDiff and /deploy/fileCompare endpoints that allows authenticated members to read arbitrary files. Attackers with repository write access can commit a symlink pointing outside the project directory to read database configuration and deployment SSH private keys.Show less

As part of Cisco's ongoing commitment to proactive security and product quality, the Cisco Expressway Series software engineering team has conducted a comprehensive internal security review. This review resulted in software hardening releases that address multiple internally discovered vulnerabilities.   The vulnerabilities tracked by CVE-2026-76496 are related to issues concerning improper link resolutions that are grouped under the Common Weakness Enumeration (CWE) Base CWE-59.Show less

Dulwich from 0.24.0 before 1.2.8 contains a symlink following vulnerability in porcelain.checkout(paths=[...]) that allows attackers to write arbitrary files by abusing raw os.open without O_NOFOLLOW. Attackers can craft a repository where a worktree symlink points to .git/hooks/post-checkout, so restoring the file from a tag writes a malicious hook for code execution.Show less

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the safe_delete() deletion error handler responds to a failed removal by reading mode bits with os.lstat(path) and applying owner-write permission with os.chmod(path, ...), which follows a symlink. A planted link inside a read-only directory can therefore cause a victim-owned target outside the destination that is initially not writable by the invoking user to become broadly writable before the retry fails, provided that user owns the target and can change its mode. Another account can use the widened mode only if it can traverse the target's parent directories; root does not reach the demonstrated failure path, and the operation does not itself read the target. This issue is fixed in version 21.14.9.Show less

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, ViaTemplateActivator._generate() removes an existing output only when Path.exists() is true, allowing a dangling symlink to survive and redirect generated activation content, while PyEnvCfg.write() opens pyvenv.cfg without first replacing an existing symbolic or hard link. Another local account that prepares final entries inside the destination can therefore cause environment creation to create or overwrite files outside the requested tree with constrained virtualenv-generated content and the invoking user's permissions. The destination parent must remain controlled by the environment owner during creation; concurrent parent-directory replacement is a separate concern. This issue is fixed in version 21.14.9.Show less

virtualenv is a tool for creating isolated virtual python environments. Prior to 21.14.9, the builtin creator calls ensure_dir() for executable, library, and package directories, and ensure_dir() accepts an existing symlink to a directory because exists() follows it. Interpreter creation, seed installation, and activation generation then write through the linked parent outside the requested destination when another local account prepared the tree and the invoking user can access the target. The --clear option removes the planted tree first, while ordinary creation reaches it; arbitrary attacker-selected output bytes are not established. This issue is fixed in version 21.14.9.Show less

Froxlor before 2.3.15 contains a symlink following vulnerability in Statistics::makeChownWithNewStats that allows authenticated customers to take ownership of arbitrary host directories by abusing the root-run traffic cron. Attackers can replace the goaccess statistics directory in their document root with a symlink, causing chown -R to hand root-owned trees to them and enabling root escalation.Show less

filelock is a platform-independent file lock for Python. From 3.20.4 until 4.2.1, ReadWriteLock let SQLite reopen the database and side files by name; on POSIX systems an attacker with rename access in a non-sticky parent can swap those names to cause overwrite or unlink operations, while a writable adjacent hot journal is additionally required for attacker-chosen content overwrites. This issue is fixed in version 4.2.1.Show less

filelock is a platform-independent file lock for Python. From 3.20.4 until 4.0.9, ReadWriteLock and AsyncReadWriteLock versions from 3.20.4 resolve the lock path and pass it to SQLite without rejecting a final symbolic link, allowing another local user who can create names in the lock directory to redirect database creation and locking or split mutual exclusion between targets. This issue is fixed in version 4.0.9.Show less

filelock is a platform-independent file lock for Python. From 4.1.0 until 4.2.1, SoftFileLock can restore a stale marker by name after moving it aside, allowing another local user with rename access in a non-sticky lock directory to swap in a symbolic link and, on a runtime that follows the link and a same-filesystem target, make the lock user hard-link one of its files into the lock directory. This issue is fixed in version 4.2.1.Show less

filelock is a platform-independent file lock for Python. From 3.32.6 until 4.2.1, SoftFileLock can follow a swapped symbolic link during the conditional os.access writability check for a node without its owner-write bit, allowing another local user on a platform and directory configuration that follows the link to infer whether a chosen path exists and is writable from the observable acquisition result. This issue is fixed in version 4.2.1.Show less

CLI Bridge provides filesystem access within a workspace root. Prior to 0.0.2, a dangling symlink pointing outside the workspace root bypasses resolveSafePath when fs.realpathSync throws ENOENT for a nonexistent target. The fallback resolves only the parent directory and returns the symlink path as safe, so write_file follows the link and can write arbitrary files outside the workspace root. This issue is fixed in version 0.0.2.Show less

A flaw was found in the rhc-canonical-facts.service systemd unit shipped with rhc. The service runs as root and operates on a file inside a directory owned by an unprivileged system user without verifying that the file is not a symbolic link. A local attacker who has already compromised the privileged yggdrasil system service account can exploit this to gain ownership of arbitrary files, leading to privilege escalation to root.Show less

A flaw was found in Nautilus. When a removable drive or disk image is unmounted or ejected, Nautilus prompts the user to empty the trash without verifying whether the trash directory paths are symbolic links. An attacker can exploit this flaw by tricking a user into mounting a crafted storage volume and confirming the prompt to empty the trash, leading to the arbitrary deletion of files accessible to that user.Show less

OpenPrinting CUPS is an open source printing system for Linux and other Unix-like operating systems. Prior to 2.4.20, copy_model() in scheduler/ipp.c creates a predictable TempDir/<connection-number>.ppd path in an lp-group-writable directory and opens it as root without O_EXCL or O_NOFOLLOW. Exploitation requires an lp-group process able to write that directory to predict the connection-derived name and plant a symlink before the root open, while a privileged add-printer or modify-printer operation using a model PPD triggers copy_model(). The reporter treats an existing lp foothold and the privileged operation as distinct prerequisites, while the maintainer assesses high privileges because installing the relevant filter or administering the printer requires root or print-administrator access. If the race succeeds, the root scheduler follows the symlink and truncates or overwrites a root-writable target with generated PPD data, compromising file integrity or availability. This issue is fixed in version 2.4.20.Show less