Weakness (CWE)
CWE-434: Unrestricted Upload of File with Dangerous Type
The product allows the upload or transfer of dangerous file types that are automatically processed within its environment.
How to prevent it (8 mitigations)
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Architecture and Design
Generate a new, unique filename for an uploaded file instead of using the user-supplied filename, so that no external input is used at all.[REF-422] [REF-423]
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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.
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Architecture and Design
Consider storing the uploaded files outside of the web document root entirely. Then, use other mechanisms to deliver the files dynamically. [REF-423]
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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.
For example, limiting filenames to alphanumeric characters can help to restrict the introduction of unintended file extensions.
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Architecture and Design
Define a very limited set of allowable extensions and only generate filenames that end in these extensions. Consider the possibility of XSS (CWE-79) before allowing .html or .htm file types.
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Implementation
Ensure that only one extension is used in the filename. Some web servers, including some versions of Apache, may process files based on inner extensions so that "filename.php.gif" is fed to the PHP interpreter.[REF-422] [REF-423]
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Implementation
When running on a web server that supports case-insensitive filenames, perform case-insensitive evaluations of the extensions that are provided.
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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.
Source: MITRE CWE-434
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High 7.5
TeamPass arbitrary file upload vulnerability
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October CMS PHP Code Execution
October CMS build 412 is vulnerable to PHP code execution in the file upload functionality resulting in site compromise and possibly other applications on the server.
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High 8.1
Unrestricted Upload of File with Dangerous Type Apache Tomcat
When running Apache Tomcat versions 9.0.0.M1 to 9.0.0, 8.5.0 to 8.5.22, 8.0.0.RC1 to 8.0.46 and 7.0.0 to 7.0.81 with HTTP PUTs enabled (e.g. via setting the readonly initialisation parameter of the Default servlet to false) it was possible to upload a JSP fil…
KEV Mar 25, 2022 -
High 8.1
When running Apache Tomcat on Windows with HTTP PUTs enabled it was possible to upload a JSP file to the server
When running Apache Tomcat 7.0.0 to 7.0.79 on Windows with HTTP PUTs enabled (e.g. via setting the readonly initialisation parameter of the Default to false) it was possible to upload a JSP file to the server via a specially crafted request. This JSP could th…
KEV Mar 25, 2022 -
High 8.8
TYPO3 Arbitrary Code Execution
Unrestricted File Upload vulnerability in the fileDenyPattern in sysext/core/Classes/Core/SystemEnvironmentBuilder.php in TYPO3 7.6.0 to 7.6.21 and 8.0.0 to 8.7.4 allows remote authenticated users to upload files with a .pht extension and consequently execute…
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High 8.8
Dolibarr ERP and CRM Unsafe File Upload Vulnerability
Dolibarr ERP/CRM 5.0.3 and prior allows low-privilege users to upload files of dangerous types, which can result in arbitrary code execution within the context of the vulnerable application.
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High 8.8
MODX Revolution allows overwriting .htaccess
In MODX Revolution before 2.5.7, a user with file upload permissions is able to execute arbitrary code by uploading a file with the name .htaccess.
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High 8.8
Moodle Unrestricted file upload vulnerability
Unrestricted file upload vulnerability in the double extension support in the "image" module in Moodle 3.1.2 allows remote authenticated users to execute arbitrary code by uploading a file with an executable extension, and then accessing it via unspecified ve…
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High —
TYPO3 doesn't properly check file extensions
The (1) file upload component and (2) File Abstraction Layer (FAL) in TYPO3 6.0.x before 6.0.8 and 6.1.x before 6.1.3 do not properly check file extensions, which allow remote authenticated editors to execute arbitrary PHP code by uploading a .php file.
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High 8.4CVE-1999-0036 Public exploit
IRIX login program with a nonzero LOCKOUT parameter allows creation or damage to files.