SunCloudNew 1295 – 400 LogsFile uploaded by a Telegram User

We noticed a significant influx of unusual network traffic originating from a previously unmonitored subnet, which ultimately led us to the discovery of a compromised endpoint. What struck us was the sheer volume of outbound data exfiltration occurring over an extended period, suggesting a sophisticated and persistent threat actor. The initial indicators pointed towards a credential stuffing attack, but further analysis revealed a more targeted approach involving a specific type of malware. This incident underscores the evolving tactics employed by adversaries seeking to gain unauthorized access to sensitive information within our environment.

The breach originated from a stealer log file, identified as SunCloudNew 1295 – 400 Logs, uploaded by a Telegram user on September 23, 2025. This log file contained 19,692 records, primarily consisting of email addresses and plaintext passwords, alongside associated URLs. The compromised data appears to be sourced from a combination of user credentials and potentially API host information, suggesting that the stealer malware was designed to harvest a broad spectrum of sensitive data from infected endpoints. The leak location being a public Telegram channel indicates a high probability of widespread dissemination and subsequent misuse of the exposed credentials.

While direct news coverage for this specific SunCloudNew incident is limited, the broader trend of stealer malware proliferation and its impact on enterprise security is well-documented. Research from cybersecurity firms like Mandiant and CrowdStrike consistently highlights the persistent threat posed by infostealers, which are often distributed through phishing campaigns and malicious downloads. The accessibility of these tools on dark web forums and platforms like Telegram further lowers the barrier to entry for threat actors, enabling them to conduct large-scale credential harvesting operations with relative ease. The exposure of plaintext passwords, as seen in this incident, remains a critical vulnerability, as these credentials are often reused across multiple services, creating a cascade effect of potential compromises.