CVE-2026-66151 in Global VPN Client
Summary
by MITRE • 08/07/2026
SonicWall Global VPN Client version 4.10.8.1108 and earlier is vulnerable to an out-of-bounds kernel memory read in the SWIPsec.sys driver, which could allow a local attacker to cause a system crash.
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Analysis
by VulDB Data Team • 08/07/2026
The SonicWall Global VPN Client represents a widely deployed network security solution that provides secure remote access capabilities for enterprise environments. This particular vulnerability affects versions 4.10.8.1108 and earlier of the client software, specifically within the SWIPsec.sys kernel driver component. The vulnerability manifests as an out-of-bounds memory read condition that occurs when processing certain input data structures within the IPSec protocol implementation. Such flaws in kernel-mode drivers pose significant risks to system stability and can potentially be exploited for more severe attacks if not properly addressed.
The technical flaw resides in the SWIPsec.sys driver's handling of memory operations during IPSec packet processing, where insufficient bounds checking allows a local attacker to manipulate memory access patterns that extend beyond allocated buffer boundaries. This type of vulnerability falls under the common weakness enumeration CWE-125 which specifically addresses out-of-bounds read conditions in software implementations. The vulnerability is particularly concerning because it operates at kernel level within the Windows operating system, where any memory corruption can lead to system instability and potential privilege escalation scenarios. When exploited, this condition causes a system crash or blue screen of death due to the kernel attempting to access invalid memory addresses.
The operational impact of this vulnerability extends beyond simple system crashes to potentially compromise the integrity of secure network communications that organizations rely upon for remote access security. Local attackers with minimal privileges can leverage this flaw to cause denial of service conditions, disrupting VPN connectivity and potentially creating windows for more sophisticated attacks. The vulnerability affects all systems running affected versions of the SonicWall Global VPN Client, making it particularly dangerous in enterprise environments where multiple users may be simultaneously connected through the same client software. Organizations using these vulnerable versions face increased risk of service disruption and potential security breaches if attackers successfully exploit this condition.
Mitigation strategies should prioritize immediate deployment of the latest SonicWall Global VPN Client patches that address this specific out-of-bounds memory read vulnerability. System administrators must conduct comprehensive inventory checks to identify all affected systems and ensure prompt patching across all endpoints. Additionally, implementing network monitoring solutions that can detect unusual memory access patterns or system crash events may provide early warning capabilities for potential exploitation attempts. The ATT&CK framework categorizes such vulnerabilities under initial access and privilege escalation techniques where local code execution can lead to broader system compromise. Organizations should also consider deploying additional security controls such as application whitelisting policies and kernel-mode protection mechanisms to reduce the attack surface. Regular vulnerability assessments and security audits of network infrastructure components remain essential for maintaining robust defenses against similar kernel-level vulnerabilities that could potentially be leveraged for more advanced persistent threats.