CVE-2018-6769 in Jiangmin
Summary
by MITRE
In Jiangmin Antivirus 16.0.0.100, the driver file (KrnlCall.sys) allows local users to cause a denial of service (BSOD) or possibly have unspecified other impact because of not validating input values from IOCtl 0x99008020.
Be aware that VulDB is the high quality source for vulnerability data.
Analysis
by VulDB Data Team • 01/02/2020
The vulnerability identified as CVE-2018-6769 affects Jiangmin Antivirus version 16.0.0.100 and represents a critical security flaw within the kernel-mode driver component known as KrnlCall.sys. This issue manifests through improper input validation mechanisms that fail to properly sanitize data received from specific IOCTL (Input/Output Control) requests, creating a pathway for malicious exploitation. The affected IOCTL code 0x99008020 serves as the primary attack vector where unvalidated input values can trigger unpredictable system behavior. The vulnerability resides at the kernel level, making it particularly dangerous as it operates with the highest privileges and can directly interact with system memory and hardware resources. This type of flaw falls under the category of improper input validation, which is commonly categorized as CWE-20 by the Common Weakness Enumeration standard. The security implications extend beyond simple denial of service since the vulnerability could potentially enable more severe consequences including privilege escalation or system compromise.
The technical execution of this vulnerability involves local attackers who can craft malicious IOCTL requests to the vulnerable driver interface. When the KrnlCall.sys driver receives the malformed input through IOCTL 0x99008020, it fails to validate the parameters before processing them, leading to potential buffer overflows, memory corruption, or other kernel-level errors. The resulting system instability typically manifests as a blue screen of death (BSOD) which effectively renders the system unusable until a reboot occurs. However, the unspecified other impacts suggest that the vulnerability may also enable additional attack vectors beyond simple system crashes. The kernel-mode nature of the driver means that any exploitation attempts can directly affect the operating system's core functionality, potentially allowing attackers to bypass security controls that normally protect against such threats. This vulnerability directly relates to the ATT&CK technique T1068 which describes the use of privilege escalation techniques to gain access to kernel-level functionality, and T1059 which covers the use of system commands to execute malicious code.
The operational impact of CVE-2018-6769 extends beyond immediate system availability concerns to encompass potential data integrity and confidentiality risks. Organizations running affected Jiangmin Antivirus versions face significant exposure since the vulnerability can be exploited by local users with minimal privileges, making it particularly concerning for enterprise environments where user access controls may be less restrictive. The vulnerability's presence in antivirus software creates a particularly dangerous scenario where security tools become potential attack vectors rather than protective mechanisms. System administrators must consider that this flaw could be leveraged by malicious insiders or attackers who have already gained local access to systems, potentially escalating their privileges or causing sustained service disruption. The BSOD impact creates significant operational downtime and requires system recovery procedures that may involve complete reinstallations of the operating system and security software. Organizations should also consider that this vulnerability may be used in conjunction with other exploits to create more sophisticated attack chains, particularly since it operates at the kernel level where many security controls are bypassed or rendered ineffective. The lack of specific details about the unspecified other impacts suggests that additional security implications may exist that could include privilege escalation capabilities or information disclosure mechanisms that could be exploited by sophisticated attackers.