CVE-2022-43688 in Concrete
Summary
by MITRE • 11/15/2022
Concrete CMS (formerly concrete5) below 8.5.10 and between 9.0.0 and 9.1.2 is vulnerable to Stored Cross-Site Scripting (XSS) in icons since the Microsoft application tile color is not sanitized. Remediate by updating to Concrete CMS 9.1.3+ or 8.5.10+.
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Analysis
by VulDB Data Team • 12/18/2022
Concrete CMS versions prior to 8.5.10 and between 9.0.0 and 9.1.2 contain a critical stored cross-site scripting vulnerability that affects the application's handling of icon data. This vulnerability stems from insufficient input sanitization when processing Microsoft application tile color specifications, allowing malicious actors to inject malicious scripts through icon uploads or configuration modifications. The flaw specifically impacts the content management system's ability to properly validate and sanitize color parameters associated with application tiles, creating a persistent XSS attack vector that can execute malicious code in the context of any user who views affected content.
The technical implementation of this vulnerability occurs within the icon processing pipeline where color values are accepted without proper validation or sanitization. When users upload icons or configure application tiles through the CMS interface, the system fails to properly escape or filter color specifications that may contain malicious script content. This stored nature of the vulnerability means that once malicious code is injected, it persists in the database and executes whenever affected pages are rendered, making it particularly dangerous for high-privilege users who may inadvertently trigger the payload. The vulnerability aligns with CWE-79, which specifically addresses cross-site scripting flaws in web applications, and represents a classic case of insufficient input validation and output encoding.
The operational impact of this vulnerability extends beyond simple script execution, as it can enable attackers to perform session hijacking, data exfiltration, and privilege escalation attacks. An attacker who successfully exploits this vulnerability could gain unauthorized access to administrative functions, modify content, steal user credentials, or redirect users to malicious sites. The stored nature of the vulnerability makes it particularly concerning for organizations that rely on CMS platforms for content management, as the attack can remain undetected for extended periods while continuously affecting visitors. This vulnerability particularly affects organizations using Concrete CMS for corporate websites, e-commerce platforms, or any system where user-generated content or administrative configuration is prevalent.
Organizations should immediately update to Concrete CMS version 9.1.3 or later, or version 8.5.10 and later, to remediate this vulnerability. The update addresses the core sanitization issue by implementing proper input validation and output encoding for color parameters in application tile configurations. Security teams should also conduct thorough audits of existing icon uploads and configuration data to identify any potential malicious payloads that may have already been injected. Additional mitigations include implementing web application firewalls, restricting administrative privileges, and monitoring user access logs for suspicious activity. The vulnerability demonstrates the importance of proper input validation in web applications and aligns with ATT&CK technique T1566.001 for credential access through social engineering via web applications. Organizations should also consider implementing content security policies and regular security assessments to prevent similar vulnerabilities from emerging in other components of their CMS infrastructure.