CVE-2018-15312 in BIG-IP
Summary
by MITRE
On F5 BIG-IP 13.0.0-13.1.1.1 and 12.1.0-12.1.3.6, a reflected Cross-Site Scripting (XSS) vulnerability exists in an undisclosed page of the BIG-IP Configuration utility that allows an authenticated user to execute JavaScript for the currently logged-in user.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 05/30/2023
The CVE-2018-15312 vulnerability represents a critical reflected cross-site scripting flaw within F5 BIG-IP configuration utilities affecting versions 12.1.0 through 12.1.3.6 and 13.0.0 through 13.1.1.1. This vulnerability resides in an undisclosed page of the BIG-IP management interface, making it particularly dangerous as attackers cannot easily predict or target the specific endpoint. The flaw operates under the Common Weakness Enumeration classification of CWE-79 which specifically addresses cross-site scripting vulnerabilities where user-provided data is reflected back to users without proper sanitization or encoding. The vulnerability specifically impacts the BIG-IP Configuration utility's authentication system, creating a scenario where an authenticated user can inject malicious JavaScript code that executes within the context of the currently logged-in user's session.
The technical exploitation of this vulnerability requires an authenticated user to be logged into the BIG-IP management interface, which significantly reduces the attack surface compared to unauthenticated XSS flaws. However, this still represents a severe security risk as it allows for privilege escalation and session hijacking attacks. When an authenticated user visits a maliciously crafted URL containing the XSS payload, the JavaScript code gets executed in their browser session, potentially allowing attackers to steal session cookies, perform unauthorized configuration changes, or redirect users to malicious websites. The reflected nature of this XSS means that the malicious script is not stored on the server but rather reflected back to the user through the application's response, making it difficult to detect through traditional security scanning methods.
The operational impact of CVE-2018-15312 extends beyond simple script execution as it fundamentally compromises the integrity of the BIG-IP management interface. An attacker with access to an authenticated session can manipulate the configuration utility to perform actions such as creating new users, modifying existing configurations, or accessing sensitive system information. This vulnerability directly violates the principle of least privilege and can lead to complete system compromise if attackers can escalate their privileges or gain access to administrative accounts. The attack vector typically involves sending a malicious link to a legitimate user within the organization, who would then inadvertently execute the malicious script upon visiting the page. This form of attack aligns with the ATT&CK framework's technique T1059.007 for command and scripting interpreter, specifically targeting web applications and browser-based attacks.
Organizations affected by this vulnerability should immediately implement several mitigation strategies to protect their F5 BIG-IP systems. The primary recommendation involves applying the official F5 security patches released in response to this vulnerability, which typically include input validation and output encoding mechanisms to prevent script injection. Network segmentation and access controls should be strengthened to limit who can access the BIG-IP management interfaces, particularly restricting access to only necessary administrative personnel. Implementing Content Security Policies (CSP) can provide additional protection by preventing execution of unauthorized scripts in the browser context. Regular security audits and monitoring of user sessions should be conducted to detect any suspicious activities that might indicate exploitation attempts. The vulnerability also highlights the importance of maintaining current security patches and implementing robust application security testing procedures to identify similar flaws in other web applications within the organization's infrastructure.