Weakness (CWE)
CWE-73: External Control of File Name or Path
The product allows user input to control or influence paths or file names that are used in filesystem operations.
How to prevent it (8 mitigations)
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Architecture and Design
When the set of filenames is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames, and reject all other inputs. For example, ID 1 could map to "inbox.txt" and ID 2 could map to "profile.txt". Features such as the ESAPI AccessReferenceMap provide this capability.
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Architecture and Design, Operation
Run your code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict all access to files within a particular directory.
Examples include the Unix chroot jail and AppArmor. In general, managed code may provide some protection.
This may not be a feasible solution, and it only limits the impact to the operating system; the rest of your application may still be subject to compromise.
Be careful to avoid CWE-243 and other weaknesses related to jails.
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Architecture and Design
For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.
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Implementation
Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does.
When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue."
Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
When validating filenames, use stringent allowlists that limit the character set to be used. If feasible, only allow a single "." character in the filename to avoid weaknesses such as CWE-23, and exclude directory separators such as "/" to avoid CWE-36. Use a list of allowable file extensions, which will help to avoid CWE-434.
Do not rely exclusively on a filtering mechanism that removes potentially dangerous characters. This is equivalent to a denylist, which may be incomplete (CWE-184). For example, filtering "/" is insufficient protection if the filesystem also supports the use of "\" as a directory separator. Another possible error could occur when the filtering is applied in a way that still produces dangerous data (CWE-182). For example, if "../" sequences are removed from the ".../...//" string in a sequential fashion, two instances of "../" would be removed from the original string, but the remaining characters would still form the "../" string.
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Implementation
Use a built-in path canonicalization function (such as realpath() in C) that produces the canonical version of the pathname, which effectively removes ".." sequences and symbolic links (CWE-23, CWE-59).
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Installation, Operation
Use OS-level permissions and run as a low-privileged user to limit the scope of any successful attack.
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Operation, Implementation
If you are using PHP, configure your application so that it does not use register_globals. During implementation, develop your application so that it does not rely on this feature, but be wary of implementing a register_globals emulation that is subject to weaknesses such as CWE-95, CWE-621, and similar issues.
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Testing
Use tools and techniques that require manual (human) analysis, such as penetration testing, threat modeling, and interactive tools that allow the tester to record and modify an active session. These may be more effective than strictly automated techniques. This is especially the case with weaknesses that are related to design and business rules.
Source: MITRE CWE-73
17 results · Clear filters · Feed
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High 7.2
Plex Media Server arbitrary file write
Plex Media Server before 1.43.3.10861 allows an admin user to write arbitrary files that may be executed on load. The preference TranscoderH264Options is appended verbatim to x264's option string on every transcode. At startup, all .so files are run without s…
KEV Oct 20, 2026 -
High 8.4CVE-2026-83603 Public exploit
Netdata: Local Root via ndsudo Arbitrary socket_path → fail2ban-client Pickle RCE
Netdata is an open source observability tool. Prior to 2.10.4, the setuid-root ndsudo helper command fail2ban-client-status-socket in src/collectors/utils/ndsudo.c accepts a caller-controlled --socket_path from the low-privileged netdata service account. The …
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High 7.2CVE-2026-90932 Public exploit
LaraDashboard 0.9.2 through 1.2.2 Path Traversal RCE
LaraDashboard versions 0.9.2 through 1.2.2 contain a path traversal vulnerability in the core-upgrade backup handling. CoreUpgradeController and BackupService (e.g. BackupService::deleteBackup()) concatenate the user-supplied backup_file/filename value direct…
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High 7.5CVE-2026-16444 Public exploit
Improper Validation of File Paths in TeamViewer Desktop Clients
Improper neutralization of path traversal sequences in TeamViewer Desktop Clients prior Version 15.81.5 allows an authenticated remote session participant to write files to unintended locations on the local file system via file transfer or virtual file clipbo…
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High 8.8CVE-2026-67920 Public exploit
An issue in Halo 2.25.4 allows a remote attacker to execute arbitrary code via the run.halo.app.migration.impl.Migratio…
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High 7.8CVE-2026-5054 Public exploit
NoMachine External Control of File Path Local Privilege Escalation Vulnerability
NoMachine External Control of File Path Local Privilege Escalation Vulnerability. This vulnerability allows local attackers to escalate privileges on affected installations of NoMachine. An attacker must first obtain the ability to execute low-privileged code…
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High 7.1CVE-2026-5053 Public exploit
NoMachine External Control of File Path Arbitrary File Deletion Vulnerability
NoMachine External Control of File Path Arbitrary File Deletion Vulnerability. This vulnerability allows local attackers to delete arbitrary files on affected installations of NoMachine. An attacker must first obtain the ability to execute low-privileged code…
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High 8.6CVE-2026-28286 Public exploit
ZimaOS: Unauthorized Creation of Files/Folders in Restricted System Directories via API
ZimaOS is a fork of CasaOS, an operating system for Zima devices and x86-64 systems with UEFI. In version 1.5.2-beta3, the application enforces restrictions in the frontend/UI to prevent users from creating files or folders in internal OS paths. However, when…
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High 7.0CVE-2026-26157 Public exploit
Busybox: busybox: arbitrary file overwrite and potential code execution via incomplete path sanitization
A flaw was found in BusyBox. Incomplete path sanitization in its archive extraction utilities allows an attacker to craft malicious archives that when extracted, and under specific conditions, may write to files outside the intended directory. This can lead t…
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High 7.5CVE-2025-8422 Public exploit
Propovoice <= 1.7.6.7 - Unauthenticated Arbitrary File Read
The Propovoice: All-in-One Client Management System plugin for WordPress is vulnerable to Arbitrary File Read in all versions up to, and including, 1.7.6.7 via the send_email() function. This makes it possible for unauthenticated attackers to read the content…
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High 8.4CVE-2011-10030 Public exploit
Foxit PDF Reader < 4.3.1.0218 JavaScript File Write
Foxit PDF Reader < 4.3.1.0218 exposes a JavaScript API function, createDataObject(), that allows untrusted PDF content to write arbitrary files anywhere on disk. By embedding a malicious PDF that calls this API, an attacker can drop executables or scripts in…
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High 8.8
Internet Shortcut Files Remote Code Execution Vulnerability
External control of file name or path in Internet Shortcut Files allows an unauthorized attacker to execute code over a network.
KEV Jun 10, 2025 -
High 7.5CVE-2025-3419 Public exploit
Event Manager, Events Calendar, Tickets, Registrations – Eventin <= 4.0.26 - Unauthenticated Arbitrary File Read
The Event Manager, Events Calendar, Tickets, Registrations – Eventin plugin for WordPress is vulnerable to arbitrary file read in all versions up to, and including, 4.0.26 via the proxy_image() function. This makes it possible for unauthenticated attackers to…
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High 8.8CVE-2024-57394 Public exploit
The quarantine - restore function in Qi-ANXIN Tianqing Endpoint Security Management System v10.0 allows user to restore…
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High 8.2CVE-2024-21545 Public exploit
Proxmox Virtual Environment is an open-source server management platform for enterprise virtualization. Insufficient sa…
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High 8.8CVE-2023-35985 Public exploit
An arbitrary file creation vulnerability exists in the Javascript exportDataObject API of Foxit Reader 12.1.3.15356 due…
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High 7.3
Boss Mini document file inclusion
A vulnerability was found in Boss Mini 1.4.0 Build 6221. It has been classified as critical. This affects an unknown part of the file boss/servlet/document. The manipulation of the argument path leads to file inclusion. It is possible to initiate the attack r…