CVE-2017-20027 in HumHub
Summary
by MITRE • 06/10/2022
A vulnerability was found in HumHub up to 1.0.1 and classified as problematic. Affected by this issue is some unknown functionality. The manipulation leads to cross site scripting (DOM). The attack may be launched remotely. The exploit has been disclosed to the public and may be used. Upgrading to version 1.1.1 is able to address this issue. It is recommended to upgrade the affected component.
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Analysis
by VulDB Data Team • 11/22/2022
The vulnerability identified as CVE-2017-20027 represents a cross site scripting flaw in HumHub versions up to 1.0.1, specifically classified as a DOM-based XSS vulnerability under the CWE-79 category. This weakness resides in the application's handling of user input within the DOM environment, where malicious scripts can be injected and executed in the context of other users' browsers. The vulnerability affects an unspecified functionality within the platform, suggesting it impacts core user interaction mechanisms that process dynamic content or user-generated data.
The technical exploitation of this vulnerability occurs through remote attack vectors, meaning malicious actors can trigger the XSS payload without requiring physical access to the system. This remote exploitability significantly increases the attack surface and potential impact, as attackers can craft malicious links or content that, when viewed by unsuspecting users, executes harmful scripts in their browser context. The DOM-based nature of the vulnerability indicates that the malicious code is executed through modifications to the Document Object Model after the page has loaded, making it particularly challenging to detect and prevent through traditional input validation approaches.
The operational impact of this vulnerability extends beyond simple data theft or session hijacking, as DOM-based XSS can enable more sophisticated attacks including credential theft, privilege escalation, and the execution of arbitrary commands within the victim's browser context. Attackers can leverage this vulnerability to impersonate legitimate users, access sensitive information, or manipulate the application's functionality in ways that persist across user sessions. The fact that this exploit has been publicly disclosed and is potentially in use underscores the urgency of remediation, as the vulnerability has likely been targeted by threat actors seeking to compromise user sessions and gain unauthorized access to the platform's resources.
Organizations utilizing affected HumHub versions should prioritize immediate upgrade to version 1.1.1 or later to address this security gap. The upgrade process should include comprehensive testing to ensure compatibility and functionality of custom modules or integrations. Additionally, implementing proper input sanitization, output encoding, and Content Security Policy headers can provide additional defense-in-depth measures. The vulnerability aligns with ATT&CK technique T1059.007 for command and scripting interpreter, as attackers may use the XSS vulnerability to execute malicious scripts in the victim's browser environment, potentially leading to further compromise through techniques such as credential harvesting or browser exploitation.