Description: Attackers inject malicious data into the content used to populate table view cells, aiming to exploit vulnerabilities in the cell's rendering or layout process. This leverages the library's dynamic height calculation.
UITableView-FDTemplateLayoutCell Contribution: The library's core function is to dynamically calculate cell heights based on this content. It directly uses the provided content to determine layout, making this content a primary attack vector. The library provides the mechanism for the attack, even if the vulnerability exists in the custom cell code.
Example: An attacker provides a specially crafted string containing format string specifiers. Because UITableView-FDTemplateLayoutCell uses this string to calculate the cell height (by rendering the cell in a template context), the vulnerable code within the custom UITableViewCell subclass (e.g., using String(format:) with untrusted input) is executed, allowing the attacker to read or write to arbitrary memory locations. Another example: injecting a very long string to cause a buffer overflow in the cell's layout code during the height calculation process.
Impact: Potential for arbitrary code execution, data corruption, application crashes, and data leakage.
Risk Severity: Critical (if code execution is possible) or High (for data corruption/crashes).
Mitigation Strategies:
* Strict Input Validation: Validate all data used to populate cells before it's used for height calculation. This includes length limits, character whitelisting/blacklisting, and format string validation. This is the most important mitigation.
* Safe String Handling: Use Swift's safe string handling features. Avoid String(format:) with untrusted input, especially in any Objective-C code.
* Secure Custom Cell Implementation: Thoroughly review and test the UITableViewCell subclass code for vulnerabilities, particularly focusing on data handling and layout logic. Use fuzz testing. This is crucial because the library relies on this custom code.
* Content Security Policy (CSP) (if using Web Views): If the cell contains a WKWebView or UIWebView, use CSP. This is relevant because the library is used to calculate the height of the web view.
* Disable JavaScript (if possible in Web Views): If JavaScript is not strictly necessary, disable it.
Attack Surface: 2. Denial of Service (DoS) via Excessive Height Calculation
Description: Attackers provide data designed to cause extremely long or complex cell height calculations, consuming excessive CPU resources and making the application unresponsive. This directly targets the library's core functionality. UITableView-FDTemplateLayoutCell Contribution: The library's dynamic height calculation is the direct target of this attack. The attacker is exploiting the library's intended behavior to cause performance issues. Example: An attacker provides data containing deeply nested views, extremely long strings with complex formatting, or images with enormous dimensions, all designed to maximize the time required for the library to calculate the cell height. The library is forced to perform these calculations. Impact: Application becomes unresponsive or crashes, denying service to legitimate users. Risk Severity: High Mitigation Strategies: * Input Validation (Length and Complexity Limits): Impose strict limits on the length of strings and the complexity of the data. Reject overly complex input before it reaches the library. * Timeout Mechanisms: Implement a timeout for the height calculation process within the library's usage. If the calculation takes too long, abort it and use a default height. * Resource Limits: Limit the complexity of the cell's layout (e.g., maximum nesting depth, maximum number of subviews) that the library will process. * Rate Limiting (if applicable): If the data is coming from a network source, implement rate limiting to prevent an attacker from flooding the application.
Description: If a cell contains a UIWebView or WKWebView (or any component that renders web content), and the attacker can control the content loaded into that web view, they could exploit vulnerabilities in the web view itself.
UITableView-FDTemplateLayoutCell Contribution: The library directly facilitates the use of UIWebView/WKWebView within cells by providing a mechanism for dynamically calculating their height. The height calculation process involves rendering the web content, making the web view's security directly relevant to the library's operation.
Example: An attacker injects malicious JavaScript code into the content loaded into a WKWebView within a cell. This JavaScript code could then steal cookies, redirect the user, or perform other malicious actions. The library is used to calculate the height of this compromised web view.
Impact: Cross-site scripting (XSS), data theft, phishing, and potentially other web-based attacks.
Risk Severity: High
Mitigation Strategies:
* Content Security Policy (CSP): Use CSP to restrict the resources that the web view can load.
* Input Sanitization (for HTML): If the web view content is generated from user input, use a robust HTML sanitizer.
* Disable JavaScript (if possible): If JavaScript is not required, disable it.
* Sandboxing: Consider using a sandboxed web view.
* Avoid UIWebView: Prefer WKWebView.
* Principle of Least Privilege: Only grant the webview the minimum necessary permissions.