CVE-2018-9330 in Coremail
Summary
by MITRE
register.jsp in Coremail XT3.0 allows stored XSS, as demonstrated by the third form field to a URI under register/, a different vulnerability than CVE-2015-6942.
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Analysis
by VulDB Data Team • 01/23/2020
The vulnerability identified as CVE-2018-9330 represents a stored cross-site scripting flaw within the Coremail XT3.0 email server software, specifically affecting the register.jsp component. This issue arises from insufficient input validation and output encoding mechanisms in the registration form processing functionality, allowing malicious actors to inject persistent malicious scripts into the application's database. The vulnerability manifests when user-supplied data from the third form field within the registration URI path is not properly sanitized before being stored and subsequently rendered back to users. Unlike CVE-2015-6942 which addressed a different vector of attack, this particular flaw demonstrates how web applications can remain susceptible to stored XSS attacks even after previous vulnerabilities have been patched, highlighting the persistent nature of input validation weaknesses in web applications.
The technical exploitation of this vulnerability occurs through the manipulation of the third form field in the register.jsp endpoint, where attackers can embed malicious JavaScript code that gets stored in the application's backend database. When other users access pages that display this stored data, the malicious script executes in their browser context, potentially leading to session hijacking, credential theft, or redirection to malicious sites. The vulnerability falls under CWE-79 which specifically addresses Cross-Site Scripting flaws, and more precisely aligns with CWE-80 which deals with improper neutralization of script-related HTML tags in a web page. The attack vector operates through the standard HTTP request processing flow where user input is directly stored without adequate sanitization, creating a persistent threat that affects all users who encounter the malicious content.
The operational impact of this stored XSS vulnerability extends beyond simple data theft, as it can enable attackers to escalate privileges within the email system and potentially compromise the entire email infrastructure. Since Coremail XT3.0 serves as an enterprise email solution, successful exploitation could lead to unauthorized access to sensitive corporate communications, email account takeovers, and potential lateral movement within the organization's network. The stored nature of the vulnerability means that the malicious payload persists even after the initial injection, making it particularly dangerous as it can affect multiple users over extended periods without requiring repeated exploitation attempts. This vulnerability aligns with ATT&CK technique T1059.007 which describes the use of scripting languages for execution, and T1566 which covers social engineering techniques that can be amplified through stored XSS attacks.
Organizations affected by CVE-2018-9330 should implement immediate mitigations including comprehensive input validation and output encoding for all user-supplied data, particularly in form processing components. The recommended approach involves sanitizing all input through established libraries and frameworks that properly handle HTML encoding, implementing Content Security Policy headers to limit script execution, and conducting thorough code reviews to identify similar patterns in other application components. Additionally, regular security testing including automated vulnerability scanning and manual penetration testing should be performed to detect and remediate similar issues before they can be exploited. The vulnerability demonstrates the critical importance of maintaining robust input validation practices throughout the entire application lifecycle, as even minor oversights in form field processing can create persistent security risks that may compromise entire systems.