CVE-2017-9861 in Solar System
Summary
by MITRE
An issue was discovered in SMA Solar Technology products. The SIP implementation does not properly use authentication with encryption: it is vulnerable to replay attacks, packet injection attacks, and man in the middle attacks. An attacker is able to successfully use SIP to communicate with the device from anywhere within the LAN. An attacker may use this to crash the device, stop it from communicating with the SMA servers, exploit known SIP vulnerabilities, or find sensitive information from the SIP communications. Furthermore, because the SIP communication channel is unencrypted, an attacker capable of understanding the protocol can eavesdrop on communications. For example, passwords can be extracted.
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Analysis
by VulDB Data Team • 08/05/2024
The vulnerability identified as CVE-2017-9861 affects SMA Solar Technology products and represents a critical weakness in the Session Initiation Protocol implementation that undermines fundamental security assurances. This flaw exists within the communication framework that enables solar energy systems to interact with monitoring servers and manage operational parameters. The vulnerability stems from improper implementation of authentication mechanisms combined with inadequate encryption protocols, creating multiple attack vectors that compromise the integrity and confidentiality of system communications.
The technical flaw manifests through the absence of proper authentication verification during SIP communication sessions, allowing attackers to exploit replay attacks where captured packets can be resent to manipulate system behavior. Additionally, the implementation fails to provide adequate protection against packet injection attacks, enabling malicious actors to inject false data into communication streams. The lack of encryption creates an environment where man-in-the-middle attacks can succeed, as attackers can intercept and manipulate communications without detection. This weakness specifically targets the Local Area Network (LAN) environment where SMA devices operate, allowing unauthorized access from any network position that can communicate with the target device.
The operational impact of this vulnerability extends beyond simple unauthorized access to include system disruption and data compromise. Attackers can crash devices, effectively causing service interruptions that may result in energy production halts or monitoring failures. The ability to prevent communication with SMA servers creates a denial of service scenario that can disable critical system management functions. Furthermore, the vulnerability enables exploitation of known SIP protocol weaknesses, potentially allowing attackers to escalate privileges or gain deeper system access. The unencrypted nature of communications means that sensitive information, including passwords and system credentials, can be easily intercepted and extracted by network monitoring tools.
Security professionals should recognize this vulnerability as a direct violation of CWE-310, which addresses cryptographic weaknesses, and aligns with ATT&CK techniques related to credential access and defense evasion. The vulnerability demonstrates poor implementation of secure communication protocols and represents a failure to apply fundamental security principles. Organizations should implement immediate mitigations including network segmentation to isolate SMA devices, deployment of intrusion detection systems to monitor for suspicious SIP traffic patterns, and implementation of secure communication channels. The remediation approach should involve firmware updates from SMA to address the authentication and encryption flaws, alongside network-level controls that restrict access to the affected devices to authorized personnel only.