China-Aligned Bronze Sandcastle Abuses Sandboxie DLL Sideloading to Deploy Backdoors
Cybersecurity researchers have disclosed details of a previously undocumented China-aligned threat cluster known as Bronze Sandcastle that has been observed targeting organizations in Asia and Africa since mid-2025. "The most distinctive technical marker for Bronze Sandcastle is its consistent use of Sandboxie DLL sideloading," Sophos security researcher Gabor Szappanos said in a post published Tuesday. Between August 2025 and August 2026, attacks mounted by the threat actor have resulted in victims in the Philippines, Taiwan, Afghanistan, Namibia, and likely South Korea. Evidence indicates that Bronze Sandcastle is most active in the UTC+8 time zone. DLL sideloading is a popular adversarial technique that exploits the way Windows loads DLL files, allowing an attacker to trick a legitimate program into loading a malicious DLL . When an application is launched, it needs to load various DLLs in order to function correctly. If the application does not provide the f...
Oct 21, 2026