CVE-2024-20474: Medium Vulnerability in Cisco Secure Client Software

A vulnerability in Internet Key Exchange version 2 (IKEv2) processing of Cisco Secure Client Software could allow an unauthenticated, remote attacker to cause a denial of service (DoS) of Cisco Secure Client. This vulnerability is due to an integer underflow condition. An attacker could exploit this vulnerability by sending a crafted IKEv2 packet to an affected system. A successful exploit could allow the attacker to cause Cisco Secure Client Software to crash, resulting in a DoS condition on the client software. Note: Cisco Secure Client Software releases 4.10 and earlier were known as Cisco AnyConnect Secure Mobility Client.

This vulnerability has been assigned a CVSS score of 4.3, indicating a medium severity level. Organizations utilizing Cisco Secure Client Software should be aware of the potential risks and take action to remediate the issue swiftly. Risk to organizations includes service disruptions due to the denial of service condition, which could impact productivity and operational capabilities.

Given the nature of this vulnerability, organizations should prioritize patching immediately. Remediation processes should be initiated to ensure that affected systems are updated to versions that address this vulnerability.

The publication date of this vulnerability is October 23, 2024, and it remains critical for organizations to assess their exposure and implement the necessary updates.

Vulnerability Details

The vulnerability allows remote attackers to exploit an integer underflow condition in the IKEv2 processing of Cisco Secure Client Software. The CVSS score of 4.3 reflects the medium severity of this issue, with an availability impact classified as low. The affected products include Cisco AnyConnect Secure Mobility Client and Cisco Secure Client.

Technical Analysis

The root cause of this vulnerability stems from an integer underflow condition that could be triggered by sending a crafted IKEv2 packet. The attack vector is network-based, requiring low complexity for execution. Attackers do not need any privileges to exploit this vulnerability, but user interaction is required. The impact on confidentiality and integrity is none, while the availability impact is low, leading to potential denial of service.

Risk & Impact Analysis

Organizations face real-world risks from potential service disruptions due to this vulnerability. The blast radius could affect all users of Cisco Secure Client Software versions prior to the patch. Organizations should assess their exposure and prioritize remediation efforts based on the medium severity rating and the potential for denial of service.

Exploitation Status

Affected Versions

Affected versions include Cisco AnyConnect Secure Mobility Client 4.9 to 4.10.x and Cisco Secure Client versions 4.10.x. Organizations should verify their installed versions against the known vulnerable configurations listed in the CVE details.

Mitigation & Remediation

Organizations should implement the necessary patches provided by Cisco to address this vulnerability. For those unable to apply the patch immediately, consider implementing network controls to limit exposure to the vulnerable services until a full remediation can take place. For further guidance on effective remediation strategies, organizations can refer to penetration testing services to identify vulnerabilities in their systems.

Detection Guidance

To detect potential exploitation attempts, organizations should monitor logs for unusual IKEv2 packet patterns or spikes in error messages related to the Cisco Secure Client Software. Additionally, behavioral anomalies in client service operation may indicate attempts to exploit this vulnerability.

AppSecure Threat Intelligence Insight

The long-term significance of CVE-2024-20474 lies in its representation of vulnerabilities associated with network protocol implementations. As organizations continue to rely on secure remote access solutions, this vulnerability emphasizes the need for robust validation and testing of security protocols. Security teams are encouraged to learn from this incident and enhance their vulnerability management practices. For comprehensive strategies and insights, refer to vulnerability management program design resources and consider adopting continuous security testing practices as outlined in the penetration testing methodology guides available.

Ultimately, organizations should remain vigilant and proactive in their approach to security, taking lessons from vulnerabilities like this to strengthen their defenses against future threats.