MacSync Stealer is a macOS-focused information stealer that relies on changing infrastructure to deliver payloads, communicate with compromised devices, and exfiltrate data. Earlier reporting by RST Cloud identified the threat through a limited set of domains and documented rapid command-and-control (C2) replacement after public disclosure.
Microsoft Defender Experts expanded that view by correlating recurring endpoints and network behaviors across the activity. This behavior-led approach connected more than 30 domains and showed that the infrastructure supported more than C2 communication, extending into active collection, staging, and exfiltration. The findings demonstrate that although domains may rotate quickly, repeated execution patterns, request characteristics, staging behavior, and upload methods provide defenders with more durable opportunities to investigate MacSync Stealer activity.
Read more…
Source: Microsoft
Sign up for the Cyber Security Review Newsletter
The latest cyber security news and insights delivered right to your inbox
Related:
- CISA, NSA, FBI warn Chinese AI firms of industrial‑scale knowledge distillation
September 9, 2026
Chinese AI companies’ core development strategy is to steal proprietary functionalities and capabilities from their US counterparts, law enforcement agencies have warned. The US Cybersecurity and Infrastructure Security Agency (CISA) has published a new security advisory, drafted jointly with the National Security Agency (NSA) and the Federal Bureau of Investigation (FBI), warning American AI companies about an ongoing “aggressive, malicious, ...
- Microsoft fixes record 964 flaws, including 2 exploited zero-days
September 9, 2026
Microsoft’s September 2026 Patch Tuesday addresses 964 CVEs, including 104 rated Critical and 860 rated Important, making it the company’s largest Patch Tuesday release on record. Microsoft lists 974 CVEs in its full September security release. However, 10 of those affect cloud services or involve fixes that Microsoft applies itself, leaving 964 vulnerabilities that customers need to patch. The ...
- MikroTik router flaws allow takeover without a password
September 8, 2026
CERT Polska warns that attackers are actively exploiting a chain of critical MikroTik RouterOS flaws to seize control of routers exposed to the internet. Although the warning comes from Poland’s national cybersecurity response team, MikroTik routers are sold worldwide, including in the US. The vulnerabilities can affect users anywhere if their router is running a vulnerable version ...
- Two major security flaws are affecting more than six million WordPress websites
September 7, 2026
More than six million WordPress users are at risk of website takeover, researchers have claimed after discovering two major vulnerabilities being exploited in the wild. Security researchers Wordfence disclosed finding two flaws, one in Elementor Pro, and one in Super Forms – two popular WordPress plugins. Elementor Pro is a commercial plugin that allows users to build websites using ...
- More than 1 million users affected in Mathspace data breach across Australia and New Zealand
September 7, 2026
More than a million people, including students, school staff, and parents, have been affected following a data breach at Mathspace, according to the learning provider. The company said, in a blog post, “unauthorised parties had accessed an internal reporting system used by Mathspace” and the exposed information included names and email addresses. It said the attackers accessed ...
- G7 tells businesses to get ready for quantum cybersecurity threats
September 7, 2026
The G7, a collection of some of the world’s most powerful economies, is urging organizations to adopt quantum-resistant encryption as soon as possible and minimize the risk of losing sensitive data to technologically advanced threat actors. Virtually every industry in the world today relies on encryption (the process of converting readable data into scrambled, unreadable data ...

