CVE-2020-36827 in XAO::Web Module
Summary
by MITRE • 03/24/2024
The XAO::Web module before 1.84 for Perl mishandles characters in JSON output during use of json-embed in Web::Action.
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Analysis
by VulDB Data Team • 03/29/2025
The CVE-2020-36827 vulnerability affects the XAO::Web module version 1.84 and earlier in Perl, specifically when utilizing the json-embed feature within Web::Action components. This issue stems from improper handling of special characters during JSON output generation, creating potential security risks for applications that rely on this module for web service responses. The vulnerability manifests when the module processes data containing certain character sequences that are not properly escaped or encoded in the JSON output, leading to malformed responses that could be exploited by malicious actors.
The technical flaw resides in the module's JSON serialization process where special characters including but not limited to quotes, backslashes, and control characters are not adequately escaped or encoded before being included in the JSON response. This improper handling creates a potential injection vector where attacker-controlled data could manipulate the JSON structure, leading to various security implications. The vulnerability is particularly concerning because JSON is widely used for data interchange between web applications and their clients, making this flaw potentially exploitable in cross-site scripting scenarios or when the JSON output is consumed by JavaScript applications.
The operational impact of this vulnerability extends beyond simple data corruption, as it can enable attackers to inject malicious content into JSON responses that are subsequently processed by client-side applications. When applications parse the malformed JSON output, they may encounter unexpected behavior that could lead to execution of unintended code or data leakage. This issue particularly affects web applications that use XAO::Web for API endpoints or AJAX responses where JSON data is critical for proper application functionality and security. The vulnerability can be exploited to bypass security controls or manipulate application behavior through carefully crafted input that triggers the improper character handling.
Mitigation strategies for CVE-2020-36827 should prioritize updating to version 1.84 or later of the XAO::Web module where the character handling issue has been resolved. Organizations should also implement input validation and sanitization measures to prevent malicious character sequences from reaching the JSON output generation components. Additionally, security monitoring should be enhanced to detect unusual JSON response patterns that might indicate exploitation attempts. This vulnerability aligns with CWE-117, which addresses improper output neutralization for logs, and could potentially map to ATT&CK techniques involving command and control communications or data manipulation through web services. Regular security assessments of Perl web applications should include verification of module versions and proper JSON encoding practices to prevent similar issues from arising in other components of the application stack.