Return to Threats

China-Aligned Bronze Sandcastle Abuses Sandboxie DLL Sideloading to Deploy Backdoors

thehackernews.com 2026-10-21 AI supply chain High
Run AI Security Assessment Talk to AI CISO

Executive Summary

Bronze Sandcastle reportedly targeted organizations in Asia and Africa by abusing Sandboxie DLL sideloading to deploy backdoors. Security and platform teams should review software supply-chain dependencies and DLL-loading behavior, particularly where these components support AI applications.

What Happened

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

Affected Products

  • Sandboxie

Vulnerability / Attack Technique

DLL sideloading

Technical Mechanism

The threat cluster reportedly uses Sandboxie DLL sideloading as its consistent technical marker. The summary states that this technique was used to deploy backdoors but does not provide further implementation details.

AI Security Category

AI-assisted attack

Part of the AI-Assisted Attacks topic.

Relevant Frameworks

MITRE ATLAS: ExecutionMITRE ATLAS: PersistenceMITRE ATLAS: Defense Evasion

RealGround Analysis

This is not described as an attack on an AI or LLM system, but the reported abuse of a software component is relevant to teams operating AI agents because those systems may depend on third-party runtimes and libraries. AI teams should maintain component visibility and assess whether DLL-loading or similar execution paths could affect agent infrastructure.

Recommended Controls

  • Maintain an inventory of third-party libraries, runtimes, and execution dependencies used by AI applications and agents.
  • Monitor and restrict unexpected DLL sideloading and unsigned-library loading on systems hosting AI workloads.
  • Use application allowlisting and code-signing validation for components that support AI services.
  • Include third-party dependency and loader abuse scenarios in AI infrastructure red-team exercises.
  • Segment AI workloads from general-purpose systems to limit the impact of backdoor deployment.

Related RealGround Service

AI Agent SBOM and LLM Mapping · or start with the free AI Agent Security Scanner.

Sources

thehackernews.com: https://thehackernews.com/2026/10/china-aligned-bronze-sandcastle-abuses.html

Summary and analysis written by RealGround from the source above; last updated 2026-10-22.

Talk to AI CISO