CVE-2018-0248 in Wireless LAN Controller
Summary
by MITRE
A vulnerability in the administrative GUI configuration feature of Cisco Wireless LAN Controller (WLC) Software could allow an aUTHENTICated, remote attacker to cause the device to reload unexpectedly during device configuration when the administrator is using this GUI, causing a denial of service (DoS) condition on an affected device. The attacker would need to have valid administrator credentials on the device. This vulnerability is due to incomplete input validation for unexpected configuration options that the attacker could submit while accessing the GUI configuration menus. An attacker could exploit these vulnerabilities by authenticating to the device and submitting crafted user input when using the administrative GUI configuration feature. A successful exploit could allow the attacker to cause the device to reload, resulting in a DoS condition. Software versions prior to 8.3.150.0, 8.5.140.0, 8.8.111.0 are affected by this vulnerability.
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Analysis
by VulDB Data Team • 09/04/2023
The vulnerability described in CVE-2018-0248 represents a critical denial of service weakness within Cisco Wireless LAN Controller software that specifically targets the administrative graphical user interface configuration functionality. This flaw exists in the way the system processes input validation when administrators interact with the GUI configuration menus, creating an avenue for authenticated attackers to manipulate the device's operational state through carefully crafted inputs. The vulnerability affects multiple software version lines including those prior to 8.3.150.0, 8.5.140.0, and 8.8.111.0, indicating a widespread exposure across several generations of Cisco WLC software releases.
The technical root cause of this vulnerability stems from incomplete input validation mechanisms within the administrative GUI configuration feature. When administrators access the configuration menus through the web interface, the system fails to properly sanitize or validate user inputs that contain unexpected configuration options. This incomplete validation creates a condition where maliciously crafted inputs can bypass normal input checking procedures and potentially trigger unexpected system behavior. The vulnerability specifically manifests when an authenticated attacker submits crafted input parameters through the GUI interface, exploiting the lack of comprehensive input validation controls that should normally prevent malformed or unexpected configuration values from being processed.
From an operational perspective, the impact of this vulnerability extends beyond simple service disruption to potentially compromise network availability and business continuity. The successful exploitation of this flaw results in an unexpected device reload or reboot, effectively creating a denial of service condition that can persist until manual intervention occurs. This type of attack is particularly concerning in enterprise environments where wireless network infrastructure serves critical business functions, as the DoS condition can disrupt wireless connectivity for numerous users and devices simultaneously. The vulnerability requires only valid administrator credentials to exploit, making it accessible to both internal malicious actors and external attackers who have obtained administrative access through other means.
The security implications of CVE-2018-0248 align with CWE-20, which describes improper input validation as a fundamental weakness in software systems. This vulnerability also maps to ATT&CK technique T1078.004 which covers valid accounts with administrative privileges for lateral movement and privilege escalation. Organizations affected by this vulnerability face significant operational risks including potential network downtime, service disruption for wireless users, and increased administrative overhead for system recovery and maintenance. The impact is particularly severe in mission-critical environments where wireless infrastructure supports essential operations and where even brief service interruptions can result in substantial business disruption.
Mitigation strategies for this vulnerability primarily focus on implementing the official software patches provided by Cisco, which address the incomplete input validation issues in the affected software versions. Organizations should prioritize immediate deployment of the relevant security updates to prevent exploitation. Additionally, implementing network segmentation and access controls can reduce the attack surface by limiting the number of users with administrative privileges and restricting access to the WLC administrative interfaces. Network monitoring should be enhanced to detect unusual reload patterns or configuration changes that might indicate exploitation attempts. Regular security assessments and vulnerability scanning should be conducted to identify other potential weaknesses in the wireless infrastructure and ensure comprehensive protection against similar vulnerabilities.