Objective: Execute Arbitrary Code OR Leak Sensitive Information (via Parsedown Exploitation)
Attacker Goal:
Execute Arbitrary Code OR Leak Sensitive Information
(via Parsedown Exploitation)
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1. Remote Code Execution (RCE) (HIGH RISK) 2. Information Disclosure (MEDIUM RISK)
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1.1 XSS via 1.2 Unsafe 1.3 Logic Bugs/ 2.2 Data
Parsedown Markdown Unintended Feature Leakage
Features Handling Interactions via
(MEDIUM) (HIGH) (MEDIUM) Markdown
(MEDIUM)
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1.1.1 Stored 1.2.1 Bypass 1.3.1 Regex DoS (ReDoS)
XSS via Sanitization
crafted via crafted
Markdown Markdown
(MEDIUM) (HIGH)
Attack Tree Path: 1. Remote Code Execution (RCE) (HIGH RISK)
- Description: The attacker successfully executes arbitrary code on the server where Parsedown is running. This gives the attacker complete control over the application and potentially the underlying server.
- Impact: Complete system compromise. This is the worst-case scenario. The attacker can steal data, modify the application, install malware, pivot to other systems, and cause significant damage.
- Likelihood: High. While Parsedown itself is designed to be secure, vulnerabilities in its parsing logic or interactions with other components could lead to RCE. The complexity of Markdown parsing increases the attack surface.
- Effort: High. Exploiting an RCE vulnerability typically requires in-depth knowledge of Parsedown's internals, memory corruption techniques, and exploit development.
- Skill Level: High (Expert). Requires advanced vulnerability research and exploitation skills.
- Detection Difficulty: Medium to High. Successful exploitation might be stealthy, but unusual server activity, crashes, or unexpected network connections could be indicators. Intrusion Detection Systems (IDS) and Web Application Firewalls (WAFs) might detect some attempts, but a sophisticated attacker could bypass them.
Attack Tree Path: 1.1 XSS via Parsedown Features (MEDIUM RISK)
- Description: The attacker injects malicious JavaScript code into the output generated by Parsedown. This code is then executed in the browser of other users who view the affected content.
- Impact: Account hijacking, session theft, website defacement, phishing attacks, distribution of malware, and theft of sensitive client-side data (cookies, local storage).
- Likelihood: Medium. Parsedown is designed to prevent XSS, but edge cases or undiscovered vulnerabilities are possible. The risk increases if the application doesn't properly sanitize Parsedown's output or if there are other vulnerabilities in the application that can be combined with a Parsedown-related XSS.
- Effort: Medium. Finding XSS vulnerabilities often involves fuzzing, manual code review, and understanding of browser security mechanisms.
- Skill Level: Medium. Requires a good understanding of XSS attack vectors and how Markdown can be manipulated to inject malicious code.
- Detection Difficulty: Medium. WAFs and browser security features (like Content Security Policy) can mitigate some XSS attacks. Monitoring for unusual client-side behavior and unexpected JavaScript execution can help.
Attack Tree Path: 1.1.1 Stored XSS via crafted Markdown (MEDIUM RISK)
- Description: The attacker injects malicious Markdown that, when parsed by Parsedown, results in stored XSS. The malicious payload is saved (e.g., in a database) and served to all users who view the content. * Impact: Same as 1.1, but with a wider reach, as the attack affects all users who view the compromised content. * Likelihood: Medium. Relies on Parsedown having an XSS vulnerability and the application not properly sanitizing the output before storing it. * Effort: Medium. Similar to 1.1. * Skill Level: Medium. Similar to 1.1. * Detection Difficulty: Medium. Similar to 1.1, but may be easier to detect through regular content audits.
Attack Tree Path: 1.2 Unsafe Markdown Handling (HIGH RISK)
- Description: The attacker crafts malicious Markdown input that bypasses Parsedown's built-in sanitization mechanisms, allowing the injection of arbitrary HTML or JavaScript.
- Impact: High, potentially leading to RCE or severe XSS. The attacker gains more control over the injected code than with a typical XSS vulnerability.
- Likelihood: High. Sanitization is inherently difficult, and it's challenging to anticipate all possible ways an attacker might try to bypass it. New bypass techniques are regularly discovered.
- Effort: Medium to High. Requires a deep understanding of Parsedown's sanitization logic and creative exploitation techniques. The attacker may need to fuzz the parser extensively to find bypasses.
- Skill Level: Medium to High. Requires expertise in web security and a strong understanding of how Markdown is parsed and converted to HTML.
- Detection Difficulty: Medium to High. Sophisticated bypasses may be difficult to detect with standard security tools. Requires careful analysis of Parsedown's output and potentially dynamic analysis of the application's behavior.
Attack Tree Path: 1.2.1 Bypass Sanitization via crafted Markdown (HIGH RISK)
This is the core of the unsafe Markdown handling, and thus inherits the HIGH risk.
Attack Tree Path: 1.3 Logic Bugs / Unintended Feature Interactions (MEDIUM RISK)
- Description: Exploiting subtle flaws in Parsedown's parsing logic or unexpected interactions between different Markdown features that don't directly involve XSS or unsafe HTML handling.
- Impact: Variable, but could lead to DoS, information disclosure, or potentially even RCE in complex scenarios.
- Likelihood: Medium. Complex software often has unintended behaviors, especially when different features interact in unexpected ways.
- Effort: High. Requires deep understanding of Parsedown's internal workings and significant experimentation.
- Skill Level: High. Requires advanced knowledge of parsing techniques, fuzzing, and potentially reverse engineering.
- Detection Difficulty: High. These bugs are often subtle and may not trigger typical security alerts. Anomaly detection and thorough code auditing are necessary.
Attack Tree Path: 1.3.1 Regex DoS (ReDoS) (MEDIUM RISK)
- Description: The attacker crafts a malicious Markdown input that exploits a regular expression vulnerability in Parsedown, causing the server to consume excessive CPU resources and become unresponsive. * Impact: Denial of Service (DoS). The application becomes unavailable to legitimate users. * Likelihood: Medium. Parsedown uses regular expressions, and ReDoS vulnerabilities are common in regex-heavy code. * Effort: Medium. Requires understanding of ReDoS vulnerabilities and the ability to craft malicious input that triggers the vulnerable regex. * Skill Level: Medium. Requires knowledge of regular expressions and their performance characteristics. * Detection Difficulty: Medium. High CPU usage and slow response times are indicators. Specialized tools can be used to detect ReDoS vulnerabilities.
Attack Tree Path: 2.2 Data Leakage via Markdown (MEDIUM RISK)
- Description: A bug in Parsedown causes it to inadvertently expose parts of the input Markdown, internal data structures, or other sensitive information in the output.
- Impact: Variable, depending on the leaked data. Could range from revealing internal file paths or server information to leaking user data or secrets if they are processed by Parsedown in an insecure way.
- Likelihood: Medium. Error handling and edge cases in parsing could lead to information leaks.
- Effort: Medium. Requires fuzzing and careful examination of output, especially error messages and unexpected output.
- Skill Level: Medium. Requires understanding of how Parsedown processes input and handles errors.
- Detection Difficulty: Medium. Requires monitoring output for unexpected content and potentially analyzing error logs.