CVE-2017-9858

CVE-2017-9858 affects SMA Solar Technology products, specifically Sunny Boy TLST-21/TL-21 and Sunny Tripower TL-10/TL-30 inverters. It allows an attacker to determine active and inactive user accounts by sending crafted packets and observing responses, which aids in subsequent attacks like brute-forcing. The vulnerability has a CVSS score of 7.5 (High) due to its network attack vector, low complexity, and high impact on confidentiality, though the vendor disputes it as a "security gap." There is no evidence of active exploitation, public exploit code, or Metasploit/Nuclei modules, but it has garnered some community discussion and media coverage.