CVE-2021-20848 in rwtxt
Summary
by MITRE • 11/24/2021
Cross-site scripting vulnerability in rwtxt versions prior to v1.8.6 allows a remote attacker to inject an arbitrary script via unspecified vectors.
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Analysis
by VulDB Data Team • 11/27/2021
This cross-site scripting vulnerability affects rwtxt versions prior to v1.8.6 and represents a critical security flaw that enables remote attackers to execute malicious scripts within the context of a victim's browser. The vulnerability stems from insufficient input validation and output encoding mechanisms within the application's text processing functionality, creating an avenue for attackers to inject malicious code through unspecified vectors that could include user-supplied content or configuration parameters. The flaw manifests when the application fails to properly sanitize or escape user-provided data before rendering it in web pages, allowing attackers to inject script payloads that execute in the victim's browser session.
The technical implementation of this vulnerability aligns with CWE-79 which specifically addresses cross-site scripting flaws where applications fail to properly validate or encode output data. This weakness creates a persistent threat vector that can be exploited across multiple attack surfaces within the rwtxt application, potentially allowing attackers to steal session cookies, perform unauthorized actions on behalf of users, or redirect victims to malicious sites. The unspecified nature of the attack vectors suggests that the vulnerability could be triggered through various input points including file uploads, configuration settings, or user-generated content processing mechanisms within the text editing framework.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable sophisticated attack chains that leverage the XSS flaw for privilege escalation or data exfiltration. Attackers could craft malicious payloads that exploit the vulnerability to access sensitive user information, manipulate application behavior, or establish persistent access through session hijacking techniques. The remote nature of the attack means that exploitation does not require physical access to the target system, making it particularly dangerous for applications that process untrusted user input. This vulnerability could be leveraged in combination with other attack techniques to create more complex threats that align with ATT&CK technique T1059.007 for command and scripting interpreter, potentially allowing attackers to execute arbitrary commands through the compromised application.
Mitigation strategies should focus on implementing comprehensive input validation and output encoding mechanisms that follow secure coding practices and industry standards such as those outlined in the OWASP Top Ten and the CERT Secure Coding Standards. The most effective immediate solution involves upgrading to rwtxt version 1.8.6 or later, which includes proper sanitization of user input and enhanced output encoding. Additional protective measures include implementing content security policies, using proper input validation libraries, and establishing robust sanitization routines for all user-provided data. Organizations should also consider deploying web application firewalls and monitoring for suspicious script injection attempts, while ensuring that all user-generated content is properly escaped before rendering in web contexts to prevent exploitation of similar vulnerabilities in the future.