CVE-2026-12858 in AV Remover
Summary
by MITRE • 09/09/2026
Improper Privilege Management vulnerability in ESET AV Remover (standalone) allows Privilege Escalation via especially crafted RPC.
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Analysis
by VulDB Data Team • 09/09/2026
The identified vulnerability represents a critical flaw within the privilege management logic of ESET Anti-Virus Remover, specifically affecting its standalone executable variant. This security weakness stems from an improper handling of access control checks during remote procedure call operations, which are fundamental to inter-process communication in Windows environments. The core issue lies in the application's failure to adequately validate whether the invoking process possesses sufficient administrative privileges before executing sensitive system-level commands or modifying protected registry keys and file structures associated with ESET security products. By neglecting these essential authorization checks at critical entry points, the software inadvertently creates a pathway for attackers to bypass standard user account control mechanisms that are designed to prevent unauthorized changes to the operating system state.
From a technical perspective, this flaw is classified under CWE-269, which denotes Improper Privilege Management. The vulnerability manifests when an attacker crafts specific RPC requests that exploit the lack of rigorous permission verification within the application's service handlers. These crafted packets are designed to trigger internal functions that require elevated rights without actually possessing those rights in the context of the calling process. This discrepancy allows a lower-privileged user or a malicious script running under such a user account to execute commands with higher privileges than intended by the system administrator. The exploitation vector relies heavily on the ability to send these specially formatted requests, which typically requires local access to the machine where the vulnerable component is installed and active.
The operational impact of this vulnerability is significant as it facilitates Local Privilege Escalation. Once successfully exploited, an attacker can gain administrative control over the affected system without needing valid administrator credentials or physical interaction with a privileged account. This level of access enables the complete compromise of the host machine's confidentiality, integrity, and availability. An adversary could install persistent backdoors, disable other security controls, exfiltrate sensitive data, or move laterally within a network if this machine serves as a pivot point. The ability to escalate privileges effectively neutralizes many defense-in-depth strategies that rely on restricting user accounts to standard permissions for daily operations.
In terms of threat modeling and industry frameworks, this vulnerability aligns with the MITRE ATT&CK technique T1068, which covers Exploitation for Privilege Escalation. The specific method of using crafted RPC calls relates to techniques involving service execution or DLL injection depending on how the exploit is implemented within the local environment. Security analysts should view this not merely as a software bug but as a fundamental design flaw in how the removal tool interacts with system-level resources and validates its own operational context against the current user's security token.
Mitigation strategies must prioritize immediate patching through official vendor channels to ensure that the updated version of ESET Anti-Virus Remover includes proper access control validations for all RPC endpoints. Until patches are applied, administrators should restrict local execution permissions for this tool to only those users who genuinely require administrative privileges and have been vetted for such access. Additionally, implementing strict application whitelisting policies can prevent unauthorized or unmodified versions of the executable from running on critical systems. Monitoring logs for unusual RPC activity originating from non-standard processes may also help in detecting attempted exploitation activities before they result in a full system compromise.