Weakness (CWE)
CWE-22: Improper Limitation of a Pathname to a Restricted Directory
The product uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory, but the product does not properly neutralize special elements within the pathname that can cause the pathname to resolve to a location that is outside of the restricted directory.
More detail
Many file operations are intended to take place within a restricted directory. By using special elements such as ".." and "/" separators, attackers can escape outside of the restricted location to access files or directories that are elsewhere on the system. One of the most common special elements is the "../" sequence, which in most modern operating systems is interpreted as the parent directory of the current location. This is referred to as relative path traversal. Path traversal also covers the use of absolute pathnames such as "/usr/local/bin" to access unexpected files. This is referred to as absolute path traversal.
How to prevent it (8 mitigations)
-
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.
-
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.
-
Implementation
Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
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). This includes:
- realpath() in C
- getCanonicalPath() in Java
- GetFullPath() in ASP.NET
- realpath() or abs_path() in Perl
- realpath() in PHP
-
Architecture and Design
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid [REF-1482].
-
Operation
Use an application firewall that can detect attacks against this weakness. It can be beneficial in cases in which the code cannot be fixed (because it is controlled by a third party), as an emergency prevention measure while more comprehensive software assurance measures are applied, or to provide defense in depth [REF-1481].
-
Architecture and Design, Operation
Run your code using the lowest privileges that are required to accomplish the necessary tasks [REF-76]. If possible, create isolated accounts with limited privileges that are only used for a single task. That way, a successful attack will not immediately give the attacker access to the rest of the software or its environment. For example, database applications rarely need to run as the database administrator, especially in day-to-day operations.
-
Architecture and Design
When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, 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 [REF-185] provide this capability.
-
Architecture and Design, Operation
Run the code in a "jail" or similar sandbox environment that enforces strict boundaries between the process and the operating system. This may effectively restrict which files can be accessed in a particular directory or which commands can be executed by the software.
OS-level examples include the Unix chroot jail, AppArmor, and SELinux. In general, managed code may provide some protection. For example, java.io.FilePermission in the Java SecurityManager allows the software to specify restrictions on file operations.
This may not be a feasible solution, and it only limits the impact to the operating system; the rest of the application may still be subject to compromise.
Be careful to avoid CWE-243 and other weaknesses related to jails.
Source: MITRE CWE-22
154 results · Clear filters · Feed
-
Critical 9.8
The vRealize Log Insight contains a Directory Traversal Vulnerability. An unauthenticated, malicious actor can inject f…
-
Critical 9.8CVE-2022-45299 Public exploit
webbrowser-rs allows attackers to access arbitrary files via supplying a crafted URL
An issue in the IpFile argument of rust-lang webbrowser-rs v0.8.2 allows attackers to access arbitrary files via supplying a crafted URL.
-
Critical 9.1CVE-2022-3782 Public exploit
Keycloak vulnerable to path traversal via double URL encoding
keycloak: path traversal via double URL encoding. A flaw was found in Keycloak, where it does not properly validate URLs included in a redirect. An attacker can use this flaw to construct a malicious request to bypass validation and access other URLs and pote…
-
Critical 9.1CVE-2022-44900 Public exploit
py7zr directory traversal vulnerability
A directory traversal vulnerability in the SevenZipFile.extractall() function of the python library py7zr v0.20.0 and earlier allows attackers to write arbitrary files via extracting a crafted 7z file.
-
Critical 9.8
An issue was discovered in Zimbra Collaboration (ZCS) 8.8.15 and 9.0. An attacker can upload arbitrary files through am…
KEV Oct 20, 2022 -
Critical 9.8
Zimbra Collaboration Suite (ZCS) 8.8.15 and 9.0 has mboximport functionality that receives a ZIP archive and extracts f…
KEV Aug 11, 2022 -
Critical 9.8
RARLAB UnRAR before 6.12 on Linux and UNIX allows directory traversal to write to files during an extract (aka unpack) …
KEV Aug 9, 2022 -
Critical 9.8
Certain WSO2 products allow unrestricted file upload with resultant remote code execution. The attacker must use a /fil…
KEV Apr 25, 2022 -
Critical 9.9CVE-2022-21675 Public exploit
Bytecode Viewer v2.10.x Zip Slip
Bytecode Viewer (BCV) is a Java/Android reverse engineering suite. Versions of the package prior to 2.11.0 are vulnerable to Arbitrary File Write via Archive Extraction (AKA "Zip Slip"). The vulnerability is exploited using a specially crafted archive that ho…
-
Critical 9.1
Path traversal in GLPI barcode plugin
Barcode is a GLPI plugin for printing barcodes and QR codes. GLPI instances version 2.x prior to version 2.6.1 with the barcode plugin installed are vulnerable to a path traversal vulnerability. This issue was patched in version 2.6.1. As a workaround, delete…
-
Critical 9.8
Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories a…
KEV Nov 3, 2021 -
Critical 9.8
The vCenter Server contains an arbitrary file upload vulnerability in the Analytics service. A malicious actor with net…
KEV Nov 3, 2021 -
Critical 9.9
SAP NetWeaver (Visual Composer 7.0 RT) versions - 7.30, 7.31, 7.40, 7.50, without restriction, an attacker authenticate…
KEV Jun 9, 2022 -
Critical 9.8
Multiple vulnerabilities leading to RCE
elFinder is an open-source file manager for web, written in JavaScript using jQuery UI. Several vulnerabilities affect elFinder 2.1.58. These vulnerabilities can allow an attacker to execute arbitrary code and commands on the server hosting the elFinder PHP c…
-
Critical 9.8
Path traversal in impacket
Multiple path traversal vulnerabilities exist in smbserver.py in Impacket through 0.9.22. An attacker that connects to a running smbserver instance can list and write to arbitrary files via ../ directory traversal. This could potentially be abused to achieve …
-
Critical 9.1
SaltStack Salt Directory Traversal vulnerability
An issue was discovered in through SaltStack Salt before 3002.5. The salt.wheel.pillar_roots.write method is vulnerable to directory traversal.
-
Critical 9.8
The vSphere Client (HTML5) contains a remote code execution vulnerability in a vCenter Server plugin. A malicious actor…
KEV Nov 3, 2021 -
Critical 9.1
Apache Flink directory traversal attack: reading remote files through the REST API
A change introduced in Apache Flink 1.11.0 (and released in 1.11.1 and 1.11.2 as well) allows attackers to read any file on the local filesystem of the JobManager through the REST interface of the JobManager process. Access is restricted to files accessible b…
KEV May 23, 2024 -
Critical 9.8CVE-2019-17640 Public exploit
Path Traversal in Eclipse Vert
In Eclipse Vert.x 3.4.x up to 3.9.4, 4.0.0.milestone1, 4.0.0.milestone2, 4.0.0.milestone3, 4.0.0.milestone4, 4.0.0.milestone5, 4.0.0.Beta1, 4.0.0.Beta2, and 4.0.0.Beta3, StaticHandler doesn't correctly processes back slashes on Windows Operating systems, allo…
-
Critical 9.1
Dell EMC OpenManage Server Administrator (OMSA) versions 9.4 and prior contain multiple path traversal vulnerabilities.…
-
Critical 9.8
In BIG-IP versions 15.0.0-15.1.0.3, 14.1.0-14.1.2.5, 13.1.0-13.1.3.3, 12.1.0-12.1.5.1, and 11.6.1-11.6.5.1, the Traffic…
KEV Nov 3, 2021 -
Critical 9.1
Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software Web Services Path Traversal Vulnerability
A vulnerability in the web services interface of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to conduct directory traversal attacks and obtain read and dele…
-
Critical 9.8
An issue was discovered in Citrix Application Delivery Controller (ADC) and Gateway 10.5, 11.1, 12.0, 12.1, and 13.0. T…
KEV Nov 3, 2021 -
Critical 9.8
This external control of file name or path vulnerability allows remote attackers to access or modify system files. To f…
KEV Jun 8, 2022 -
Critical 9.8
This external control of file name or path vulnerability allows remote attackers to access or modify system files. To f…
KEV Jun 8, 2022 -
Critical 9.8
Directory Traversal in the function http_verify in nostromo nhttpd through 1.9.6 allows an attacker to achieve remote c…
KEV Nov 7, 2024 -
Critical 9.1
An Improper Limitation of a Pathname to a Restricted Directory ("Path Traversal") in Fortinet FortiOS 6.0.0 to 6.0.4, 5…
KEV Nov 3, 2021 -
Critical 9.9
In Pulse Secure Pulse Connect Secure (PCS) 8.2 before 8.2R12.1, 8.3 before 8.3R7.1, and 9.0 before 9.0R3.4, an unauthen…
KEV Nov 3, 2021 -
Critical 9.8
The Widget Connector macro in Atlassian Confluence Server before version 6.6.12 (the fixed version for 6.6.x), from ver…
KEV Nov 3, 2021 -
Critical 9.8CVE-2018-12542 Public exploit
Eclipse Vert.x does not properly neutralize '' (forward slashes) sequences that can resolve to an external location
In version from 3.0.0 to 3.5.3 of Eclipse Vert.x, the StaticHandler uses external input to construct a pathname that should be within a restricted directory, but it does not properly neutralize '\' (forward slashes) sequences that can resolve to a location th…
-
Critical 9.1
MikroTik RouterOS through 6.42 allows unauthenticated remote attackers to read arbitrary files and remote authenticated…
KEV Dec 1, 2021 -
Critical 9.8
InduSoft Web Studio Path Traversal
Directory traversal vulnerability in NTWebServer in InduSoft Web Studio 7.1 before SP2 Patch 4 allows remote attackers to read administrative passwords in APP files, and consequently execute arbitrary code, via unspecified web requests.
KEV Apr 15, 2022 -
Critical 9.8
_functions.php in cpCommerce 1.2.x, possibly including 1.2.9, sends a redirect but does not exit when it is called dire…
-
Critical 9.8
Directory traversal vulnerability in the (1) extract and (2) extractall functions in the tarfile module in Python allow…