CVE-2026-14948 in FDS
Summary
by MITRE • 08/20/2026
A low privileged remote attacker can hijack an active administrative session without needing to know the administrator password by extracting live plaintext session identifiers for authenticated users from downloadable error log archives.
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Analysis
by VulDB Data Team • 08/20/2026
The vulnerability described represents a critical failure in session management and secure logging practices, allowing unauthenticated or low-privileged attackers to escalate privileges to that of an administrator. This flaw is rooted in the improper handling of sensitive authentication data within system logs, specifically through the exposure of plaintext session identifiers. In many web applications and administrative interfaces, sessions are maintained using tokens such as cookies or URL parameters that serve as proof of identity for a specific user during their interaction with the service. When these systems generate error logs to aid in debugging or auditing, they often inadvertently capture full request headers or query strings which may contain these session identifiers. If these log files are then made available for download by users who have access to view general system information but lack administrative privileges, a significant security boundary is breached. The attacker does not need to crack passwords or exploit complex injection flaws; instead, they simply retrieve the archived logs and extract the active session tokens associated with currently logged-in administrators.
This type of vulnerability aligns closely with CWE-524, which categorizes the exposure of sensitive information in log files as a weakness. The core technical flaw lies in the lack of sanitization or redaction mechanisms within the logging subsystem. Secure coding standards dictate that authentication credentials and session tokens must never be written to persistent storage unless they are cryptographically hashed and salted, ensuring that even if the logs are compromised, the original values cannot be reconstructed. In this scenario, the system fails to distinguish between operational data and sensitive security context, treating all input as safe for logging purposes. This oversight creates a direct path for session hijacking, where an attacker can impersonate any user whose session token is present in the log file at the time of extraction. The risk is exacerbated if the logs are stored with broad read permissions or if the download functionality does not enforce strict access controls based on role-based policies rather than just general authentication status.
From a tactical perspective, this vulnerability maps directly to several techniques within the MITRE ATT&CK framework. It falls under Initial Access via Valid Accounts and specifically relates to Session Hijacking, where an adversary takes over an existing session rather than creating a new one through brute force or credential stuffing. The exploitation path involves Reconnaissance followed by Resource Development, as the attacker gathers intelligence on active sessions before leveraging that data for privilege escalation. Once the administrator's session token is obtained, the attacker can perform actions such as modifying system configurations, accessing sensitive databases, or installing backdoors without triggering password-based alerts. This bypasses traditional authentication controls and makes detection significantly more difficult because the activity appears to originate from a legitimate administrative account rather than an external threat actor.
The operational impact of this vulnerability is severe, potentially leading to complete compromise of the affected system. An attacker with hijacked administrative access can exfiltrate confidential data, alter application logic, or disrupt services at will. Because the attack relies on stealing existing sessions, it does not leave typical traces associated with brute-force attacks or injection attempts, making forensic analysis challenging unless specific session monitoring and anomaly detection are in place. Furthermore, if multiple administrators have active sessions logged within the same archive, a single download can compromise all of them simultaneously, amplifying the blast radius of the incident. This is particularly dangerous in environments where administrative accounts hold keys to critical infrastructure or sensitive customer data.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. Immediately, organizations should review log configurations to ensure that no authentication-related fields, including session IDs, cookies, tokens, or passwords, are written to logs. This often involves configuring the application framework or web server to mask these specific headers before they reach the logging subsystem. Additionally, access controls on downloadable files must be strictly enforced so that only users with explicit administrative privileges can view or download sensitive log archives. Implementing role-based access control ensures that low-privileged users cannot retrieve data containing high-value secrets regardless of other system vulnerabilities.
Long-term fixes should include implementing secure session management practices such as using HttpOnly and Secure flags on cookies, rotating session identifiers after privilege changes, and ensuring logs are stored in restricted directories with minimal permissions. Regular security audits and code reviews focused on logging mechanisms can help identify similar oversights before they are exploited. Employing a Web Application Firewall may also provide some protection by detecting unusual patterns of log access or session token usage, although it should not be relied upon as the primary defense against this class of vulnerability. Ultimately, adhering to principles like least privilege and secure defaults in logging configurations is essential to preventing unauthorized session hijacking through exposed logs.