CVE-2024-34697 in freescout
Summary
by MITRE • 05/14/2024
FreeScout is a free, self-hosted help desk and shared mailbox. A stored HTML Injection vulnerability has been identified in the Email Receival Module of the Freescout Application. The vulnerability allows attackers to inject malicious HTML content into emails sent to the application's mailbox. This vulnerability arises from improper handling of HTML content within incoming emails, allowing attackers to embed malicious HTML code in the context of the application's domain. Unauthenticated attackers can exploit this vulnerability to inject malicious HTML content into emails. This could lead to various attacks such as form hijacking, application defacement, or data exfiltration via CSS injection. Although unauthenticated attackers are limited to HTML injection, the consequences can still be severe. Version 1.8.139 implements strict input validation and sanitization mechanisms to ensure that any HTML content received via emails is properly sanitized to prevent malicious HTML injections.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 03/30/2025
The vulnerability identified as CVE-2024-34697 affects FreeScout, a self-hosted help desk and shared mailbox application that serves as a critical communication infrastructure for organizations managing customer support workflows. This stored HTML injection flaw exists within the Email Receival Module, representing a significant security weakness that directly impacts the application's email processing capabilities. The vulnerability specifically manifests when the system receives incoming emails containing malicious HTML content, creating a persistent threat vector that can compromise the application's integrity and user experience. The flaw stems from inadequate input validation and sanitization mechanisms within the email handling pipeline, allowing attackers to embed malicious code that executes within the context of the application's domain. This creates a dangerous scenario where legitimate users may encounter compromised email interfaces, potentially leading to widespread security implications throughout the organization's support infrastructure.
The technical exploitation of this vulnerability occurs through the improper handling of HTML content in incoming emails, where the application fails to adequately sanitize user-supplied content before processing or displaying it. Attackers can craft malicious emails containing embedded HTML code that gets stored and subsequently rendered within the FreeScout interface, creating a persistent threat that remains active until the application is properly updated. The vulnerability's impact extends beyond simple content manipulation, as it enables sophisticated attack vectors including form hijacking where legitimate user input forms can be manipulated to capture sensitive information, application defacement that compromises the visual integrity of the help desk interface, and data exfiltration through CSS injection techniques that can steal cookies or redirect users to malicious sites. This stored nature of the vulnerability means that once exploited, the malicious content remains active and can affect multiple users over time, creating a sustained threat that is particularly dangerous in shared or multi-user environments.
The operational impact of CVE-2024-34697 represents a significant risk to organizations relying on FreeScout for customer support operations, as it creates potential entry points for advanced persistent threats and social engineering attacks. Unauthenticated attackers can leverage this vulnerability without requiring prior access credentials, making it particularly concerning for organizations that do not implement additional security controls around email processing. The consequences can range from minor service disruption through application defacement to more serious data compromise scenarios where user credentials or sensitive customer information could be captured through form hijacking techniques. Organizations using FreeScout in production environments face the risk of reputational damage when users encounter compromised interfaces, as well as potential regulatory compliance issues if customer data is exposed through these attack vectors. The vulnerability also impacts the trust relationship between organizations and their customers, as compromised help desk interfaces can lead to phishing attempts or other social engineering attacks that exploit user confidence in legitimate support channels.
The mitigation strategy for this vulnerability involves implementing comprehensive input validation and sanitization measures within the Email Receival Module, as demonstrated by the version 1.8.139 release that addresses the issue through strict content filtering mechanisms. Organizations should prioritize immediate deployment of the patched version to prevent exploitation of this vulnerability in their environments. Additional defensive measures include implementing email filtering solutions that can detect and block suspicious HTML content before it reaches the FreeScout application, establishing network-level controls to monitor for anomalous email traffic patterns, and conducting regular security assessments of email handling processes. The fix implemented in version 1.8.139 follows established security principles that align with common weakness enumeration standards, specifically addressing CWE-79 which covers Cross-site Scripting vulnerabilities through proper input sanitization and output encoding mechanisms. Security teams should also consider implementing monitoring solutions that can detect unusual patterns in email processing or content rendering that might indicate exploitation attempts, while maintaining awareness of related attack techniques documented in the attack tactic and technique framework for command and control operations through web-based interfaces.