7 CVE-2025-26633

An attacker utilizes crafted XML user-controllable input to probe, attack, and inject data into the XML database, using techniques similar to SQL injection. The user-controllable input can allow for unauthorized viewing of data, bypassing authentication or the front-end application for direct XML database access, and possibly altering database information. [Survey the Target] Using a browser or an automated tool, an adversary records all instances of user-controllable input used to contruct XML queries [Determine the Structure of Queries] Using manual or automated means, test inputs found for XML weaknesses. [Inject Content into XML Queries] Craft malicious content containing XML expressions that is not validated by the application and is executed as part of the XML queries.

Inter-component protocols are used to communicate between different software and hardware modules within a single computer. Common examples are: interrupt signals and data pipes. Subverting the protocol can allow an adversary to impersonate others, discover sensitive information, control the outcome of a session, or perform other attacks. This type of attack targets invalid assumptions that may be inherent in implementers of the protocol, incorrect implementations of the protocol, or vulnerabilities in the protocol itself.

Data Interchange Protocols are used to transmit structured data between entities. These protocols are often specific to a particular domain (B2B: purchase orders, invoices, transport logistics and waybills, medical records). They are often, but not always, XML-based. Subverting the protocol can allow an adversary to impersonate others, discover sensitive information, control the outcome of a session, or perform other attacks. This type of attack targets invalid assumptions that may be inherent in implementers of the protocol, incorrect implementations of the protocol, or vulnerabilities in the protocol itself.

An adversary manipulates a web service related protocol to cause a web application or service to react differently than intended. This can either be performed through the manipulation of call parameters to include unexpected values, or by changing the called function to one that should normally be restricted or limited. By leveraging this pattern of attack, the adversary is able to gain access to data or resources normally restricted, or to cause the application or service to crash.

Simple Object Access Protocol (SOAP) is used as a communication protocol between a client and server to invoke web services on the server. It is an XML-based protocol, and therefore suffers from many of the same shortcomings as other XML-based protocols. Adversaries can make use of these shortcomings and manipulate the content of SOAP paramters, leading to undesirable behavior on the server and allowing the adversary to carry out a number of further attacks. [Find target application] The adversary needs to identify an application that uses SOAP as a communication protocol. [Detect Incorrect SOAP Parameter Handling] The adversary tampers with the SOAP message parameters and looks for indications that the tampering caused a change in behavior of the targeted application. [Manipulate SOAP parameters] The adversary manipulates SOAP parameters in a way that causes undesirable behavior for the server. This can result in denial of service, information disclosure, arbitrary code exection, and more.

Some APIs will strip certain leading characters from a string of parameters. An adversary can intentionally introduce leading "ghost" characters (extra characters that don't affect the validity of the request at the API layer) that enable the input to pass the filters and therefore process the adversary's input. This occurs when the targeted API will accept input data in several syntactic forms and interpret it in the equivalent semantic way, while the filter does not take into account the full spectrum of the syntactic forms acceptable to the targeted API. [Survey the application for user-controllable inputs] Using a browser, an automated tool or by inspecting the application, an adversary records all entry points to the application. [Probe entry points to locate vulnerabilities] The adversary uses the entry points gathered in the "Explore" phase as a target list and injects various leading 'Ghost' character sequences to determine how to application filters them. [Bypass input filtering] Using what the adversary learned about how the application filters input data, they craft specific input data that bypasses the filter. This can lead to directory traversal attacks, arbitrary shell command execution, corruption of files, etc.

An attacker supplies the target software with input data that contains sequences of special characters designed to bypass input validation logic. This exploit relies on the target making multiples passes over the input data and processing a "layer" of special characters with each pass. In this manner, the attacker can disguise input that would otherwise be rejected as invalid by concealing it with layers of special/escape characters that are stripped off by subsequent processing steps. The goal is to first discover cases where the input validation layer executes before one or more parsing layers. That is, user input may go through the following logic in an application: <parser1> --> <input validator> --> <parser2>. In such cases, the attacker will need to provide input that will pass through the input validator, but after passing through parser2, will be converted into something that the input validator was supposed to stop. [Determine application/system inputs where bypassing input validation is desired] The attacker first needs to determine all of the application's/system's inputs where input validation is being performed and where they want to bypass it. [Determine which character encodings are accepted by the application/system] The attacker then needs to provide various character encodings to the application/system and determine which ones are accepted. The attacker will need to observe the application's/system's response to the encoded data to determine whether the data was interpreted properly. [Combine multiple encodings accepted by the application.] The attacker now combines encodings accepted by the application. The attacker may combine different encodings or apply the same encoding multiple times. [Leverage ability to bypass input validation] Attacker leverages their ability to bypass input validation to gain unauthorized access to system. There are many attacks possible, and a few examples are mentioned here.

An attacker makes use of Cascading Style Sheets (CSS) injection to steal data cross domain from the victim's browser. The attack works by abusing the standards relating to loading of CSS: 1. Send cookies on any load of CSS (including cross-domain) 2. When parsing returned CSS ignore all data that does not make sense before a valid CSS descriptor is found by the CSS parser.

An adversary embeds one or more null bytes in input to the target software. This attack relies on the usage of a null-valued byte as a string terminator in many environments. The goal is for certain components of the target software to stop processing the input when it encounters the null byte(s). [Survey the application for user-controllable inputs] Using a browser, an automated tool or by inspecting the application, an adversary records all entry points to the application. [Probe entry points to locate vulnerabilities] The adversary uses the entry points gathered in the "Explore" phase as a target list and injects postfix null byte(s) to observe how the application handles them as input. The adversary is looking for areas where user input is placed in the middle of a string, and the null byte causes the application to stop processing the string at the end of the user input. [Remove data after null byte(s)] After determined entry points that are vulnerable, the adversary places a null byte(s) such that they remove data after the null byte(s) in a way that is beneficial to them.

If a string is passed through a filter of some kind, then a terminal NULL may not be valid. Using alternate representation of NULL allows an adversary to embed the NULL mid-string while postfixing the proper data so that the filter is avoided. One example is a filter that looks for a trailing slash character. If a string insertion is possible, but the slash must exist, an alternate encoding of NULL in mid-string may be used. [Survey the application for user-controllable inputs] Using a browser, an automated tool or by inspecting the application, an adversary records all entry points to the application. [Probe entry points to locate vulnerabilities] The adversary uses the entry points gathered in the "Explore" phase as a target list and injects postfix null byte(s) followed by a backslash to observe how the application handles them as input. The adversary is looking for areas where user input is placed in the middle of a string, and the null byte causes the application to stop processing the string at the end of the user input. [Remove data after null byte(s)] After determined entry points that are vulnerable, the adversary places a null byte(s) followed by a backslash such that they bypass an input filter and remove data after the null byte(s) in a way that is beneficial to them.

This attack targets the encoding of the URL combined with the encoding of the slash characters. An attacker can take advantage of the multiple ways of encoding a URL and abuse the interpretation of the URL. A URL may contain special character that need special syntax handling in order to be interpreted. Special characters are represented using a percentage character followed by two digits representing the octet code of the original character (%HEX-CODE). For instance US-ASCII space character would be represented with %20. This is often referred as escaped ending or percent-encoding. Since the server decodes the URL from the requests, it may restrict the access to some URL paths by validating and filtering out the URL requests it received. An attacker will try to craft an URL with a sequence of special characters which once interpreted by the server will be equivalent to a forbidden URL. It can be difficult to protect against this attack since the URL can contain other format of encoding such as UTF-8 encoding, Unicode-encoding, etc. The attacker accesses the server using a specific URL. The attacker tries to encode some special characters in the URL. The attacker find out that some characters are not filtered properly. The attacker crafts a malicious URL string request and sends it to the server. The server decodes and interprets the URL string. Unfortunately since the input filtering is not done properly, the special characters have harmful consequences.

Blind SQL Injection results from an insufficient mitigation for SQL Injection. Although suppressing database error messages are considered best practice, the suppression alone is not sufficient to prevent SQL Injection. Blind SQL Injection is a form of SQL Injection that overcomes the lack of error messages. Without the error messages that facilitate SQL Injection, the adversary constructs input strings that probe the target through simple Boolean SQL expressions. The adversary can determine if the syntax and structure of the injection was successful based on whether the query was executed or not. Applied iteratively, the adversary determines how and where the target is vulnerable to SQL Injection. [Hypothesize SQL queries in application] [Determine how to inject information into the queries] [Determine user-controllable input susceptible to injection] Determine the user-controllable input susceptible to injection. For each user-controllable input that the adversary suspects is vulnerable to SQL injection, attempt to inject the values determined in the previous step. If an error does not occur, then the adversary knows that the SQL injection was successful. [Determine database type] Determines the type of the database, such as MS SQL Server or Oracle or MySQL, using logical conditions as part of the injected queries [Extract information about database schema] Extract information about database schema by getting the database to answer yes/no questions about the schema. [Exploit SQL Injection vulnerability] Use the information obtained in the previous steps to successfully inject the database in order to bypass checks or modify, add, retrieve or delete data from the database

This attack targets the use of the backslash in alternate encoding. An adversary can provide a backslash as a leading character and causes a parser to believe that the next character is special. This is called an escape. By using that trick, the adversary tries to exploit alternate ways to encode the same character which leads to filter problems and opens avenues to attack. [Survey the application for user-controllable inputs] Using a browser, an automated tool or by inspecting the application, an adversary records all entry points to the application. [Probe entry points to locate vulnerabilities] The adversary uses the entry points gathered in the "Explore" phase as a target list and attempts to escape multiple different special characters using a backslash. [Manipulate input] Once the adversary determines how to bypass filters that filter out special characters using an escaped slash, they will manipulate the user input in a way that is not intended by the application.

This attack targets the encoding of the Slash characters. An adversary would try to exploit common filtering problems related to the use of the slashes characters to gain access to resources on the target host. Directory-driven systems, such as file systems and databases, typically use the slash character to indicate traversal between directories or other container components. For murky historical reasons, PCs (and, as a result, Microsoft OSs) choose to use a backslash, whereas the UNIX world typically makes use of the forward slash. The schizophrenic result is that many MS-based systems are required to understand both forms of the slash. This gives the adversary many opportunities to discover and abuse a number of common filtering problems. The goal of this pattern is to discover server software that only applies filters to one version, but not the other. [Survey the application for user-controllable inputs] Using a browser, an automated tool or by inspecting the application, an adversary records all entry points to the application. [Probe entry points to locate vulnerabilities] The adversary uses the entry points gathered in the "Explore" phase as a target list and looks for areas where user input is used to access resources on the target host. The adversary attempts different encodings of slash characters to bypass input filters. [Traverse application directories] Once the adversary determines how to bypass filters that filter out slash characters, they will manipulate the user input to include slashes in order to traverse directories and access resources that are not intended for the user.

An attacker can craft special user-controllable input consisting of XPath expressions to inject the XML database and bypass authentication or glean information that they normally would not be able to. XPath Injection enables an attacker to talk directly to the XML database, thus bypassing the application completely. XPath Injection results from the failure of an application to properly sanitize input used as part of dynamic XPath expressions used to query an XML database. [Survey the target] Using a browser or an automated tool, an adversary records all instances of user-controllable input used to contruct XPath queries. [Determine the tructure of queries] Using manual or automated means, test inputs found for XPath weaknesses. [Inject content into XPath query] Craft malicious content containing XPath expressions that is not validated by the application and is executed as part of the XPath queries.

This attack utilizes XQuery to probe and attack server systems; in a similar manner that SQL Injection allows an attacker to exploit SQL calls to RDBMS, XQuery Injection uses improperly validated data that is passed to XQuery commands to traverse and execute commands that the XQuery routines have access to. XQuery injection can be used to enumerate elements on the victim's environment, inject commands to the local host, or execute queries to remote files and data sources. [Survey the application for user-controllable inputs] Using a browser or an automated tool, an attacker follows all public links and actions on a web site. They record all the links, the forms, the resources accessed and all other potential entry-points for the web application. [Determine user-controllable input susceptible to injection] Determine the user-controllable input susceptible to injection. For each user-controllable input that the attacker suspects is vulnerable to XQL injection, attempt to inject characters that have special meaning in XQL. The goal is to create an XQL query with an invalid syntax. [Information Disclosure] The attacker crafts and injects an XQuery payload which is acted on by an XQL query leading to inappropriate disclosure of information. [Manipulate the data in the XML database] The attacker crafts and injects an XQuery payload which is acted on by an XQL query leading to modification of application data.