CVE-2026-9161 in Website Template
Summary
by MITRE • 09/10/2026
Observable response discrepancy vulnerability in DernekPlus Website Template allows Account Footprinting.
This issue affects Website Template: through 10092026. NOTE: The vendor was contacted early about this disclosure but did not respond in any way.
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Analysis
by VulDB Data Team • 09/10/2026
The DernekPlus website template contains a critical information disclosure vulnerability that facilitates account footprinting, allowing attackers to enumerate valid user accounts within the application infrastructure. This flaw stems from an observable discrepancy in how the system responds to authentication attempts for existing versus non-existing usernames or email addresses. In secure web applications, error handling should be uniform regardless of whether the input corresponds to a registered entity, thereby preventing adversaries from leveraging response variations as reconnaissance signals. However, due to improper implementation of validation logic within this template, the application returns distinct HTTP status codes, different message bodies, or varying latency times when an invalid username is submitted compared to one that exists in the database but has incorrect credentials. This behavior creates a side channel through which attackers can systematically probe for valid accounts without needing prior knowledge of specific user identities.
From a technical perspective, this vulnerability aligns with CWE-203: Observable Discrepanancy and CWE-204: Observable Response Discrepancy, as the application leaks internal state information through its external behavior rather than explicit data exposure. The operational impact is significant because account enumeration serves as the foundational step for more severe attacks such as credential stuffing, brute force password guessing, or targeted phishing campaigns. By identifying which email addresses are registered with the service, threat actors can prioritize their efforts on high-value targets and increase the success rate of subsequent authentication-based exploits. Since this issue affects versions through October 9, 2026, any deployment utilizing these iterations remains exposed to automated scanning tools that specialize in user enumeration techniques.
In terms of attack classification under industry frameworks, this vulnerability maps directly to MITRE ATT&CK technique T1589: Gather Victim Identity Information, specifically the sub-technique of Account Enumeration. Attackers utilize this capability during the initial reconnaissance phase to build a list of potential victims before launching targeted attacks against those accounts. The lack of vendor response further exacerbates the risk profile for organizations relying on this template, as there is no official patch or mitigation guidance available from the original developers. Consequently, system administrators and security engineers must implement compensating controls at the infrastructure level rather than waiting for a code fix.
To mitigate this vulnerability, it is essential to standardize all authentication error responses so that they appear identical regardless of whether the username exists in the database. This can be achieved by configuring the application logic to return a generic message such as "Invalid username or password" with consistent HTTP status codes and response times for both scenarios. Additionally, implementing rate limiting on login endpoints will slow down automated enumeration attempts, making large-scale footprinting operations impractical due to time constraints and detection risks. Deploying Web Application Firewalls (WAFs) configured to detect patterns indicative of user enumeration attacks can also provide an additional layer of defense by blocking suspicious request volumes or anomalous response behaviors associated with this type of reconnaissance activity.