CVE-2026-85544 in DS-KV9503
Summary
by MITRE • 09/10/2026
There is an Improper Encryption Configuration Vulnerability in some Hikvision Intercom Products. This could allow attackers to forge M1 cards.
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Analysis
by VulDB Data Team • 09/10/2026
The vulnerability identified as an improper encryption configuration within certain Hikvision intercom products represents a critical failure in the implementation of cryptographic controls for access control systems. These devices, which serve as gateways for physical security by managing entry permissions via proximity cards, rely on specific radio frequency identification protocols to authenticate users. The core technical flaw lies in the handling of M1 cards, also known as ISO 14443 Type A smart cards or Mifare Classic cards. While these systems are designed to use encrypted sectors for storing sensitive access data and user credentials, the implementation fails to enforce strict cryptographic validation during the authentication process. This misconfiguration allows an attacker with a compatible RFID reader and writing capabilities to bypass the intended security mechanisms by forging valid-looking card identifiers without possessing the correct encryption keys or undergoing proper mutual authentication procedures.
From a technical perspective, Mifare Classic cards utilize a proprietary cipher called Crypto-1, which has been known for years to be susceptible to various attacks if not implemented with additional safeguards such as key rotation and secure channel establishment. In this specific vulnerability context, the intercom device likely accepts card identifiers or authentication responses that do not meet the expected cryptographic strength requirements. An attacker can exploit this by using software tools to clone existing valid cards or generate new ones with forged identification numbers. Because the system does not adequately verify the integrity of the encrypted data sectors during the handshake process between the card and the reader, it grants access based on superficially correct but cryptographically weak credentials. This effectively neutralizes the security benefit provided by encryption, reducing the protection to a simple identifier check that can be easily replicated or spoofed.
The operational impact of this vulnerability is significant for organizations relying on these intercom systems for perimeter and entry control. Successful exploitation allows unauthorized individuals to gain physical access to restricted areas without detection through traditional means such as failed login attempts or alarm triggers, since the forged card appears valid to the system. This compromises the confidentiality and integrity of the physical security infrastructure. Attackers can use this capability to conduct surveillance, steal assets, plant malicious devices, or facilitate further network intrusion if the intercom is connected to broader IT systems that share trust relationships with the access control database. The ease of forging M1 cards means that once an attacker obtains a single valid card from an employee or resident, they can create unlimited copies, leading to widespread unauthorized access until the vulnerability is remediated and affected credentials are rotated.
This flaw aligns closely with CWE-327, which describes the use of a broken or risky cryptographic algorithm, as well as CWE-918 regarding Server-Side Request Forgery if the exploitation involves manipulating server-side validation logic through crafted card data. In terms of the MITRE ATT&CK framework, this vulnerability facilitates Initial Access via Valid Accounts (T1078) and specifically leverages techniques related to Peripheral Device Discovery and Exploitation (T1205). The attacker effectively uses stolen or forged credentials to bypass authentication controls, which is a common tactic in physical security breaches that often precede more severe cyber incidents.
Mitigation strategies must focus on both immediate remediation and long-term architectural improvements. Administrators should immediately update the firmware of affected Hikvision intercom products to versions that patch this improper encryption configuration. If an official patch is not yet available, temporary mitigations include disabling remote access features if they are enabled but unnecessary, restricting physical access to the devices themselves to prevent tampering with hardware components like RFID readers, and implementing additional layers of authentication such as PIN codes or biometric verification for high-security areas. Long-term solutions involve migrating away from legacy Mifare Classic technology toward more secure standards such as DESFire EV2 or EV3 cards, which offer stronger cryptographic primitives and mutual authentication capabilities that are resistant to cloning and forgery attacks. Regular security audits of access control systems should also be conducted to ensure that encryption keys are rotated frequently and that configuration settings adhere to industry best practices for physical cybersecurity.