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Hackers Use Claude and GPT-Powered Tools to Help Breach Government and Financial Networks

Unit 42 links two Latin America campaigns where operators used Claude and GPT-4.1 during intrusions against government and financial targets.

Palo Alto Networks Unit 42 identified two activity clusters, CL-CRI-1131 and CL-CRI-1163, tied by shared SOCKS5 relay infrastructure and use of large language models during operations. The Mexican cluster targeted a transportation organization, federal ministries and water utilities in Mexico and Ecuador, while the Brazilian cluster used resume-themed phishing, custom remote-access Trojans and SockTz SOCKS5 tunneling against financial organizations. An exposed self-hosted NextChat interface on attacker infrastructure led researchers to assess operators used Claude and GPT-4.1 to generate workaround scripts and troubleshoot execution failures. Unit 42 noted AI reduced time needed to troubleshoot intrusions after initial access, rather than replacing the attacker.

Cyber Security Newsupdated · 5d agofirst · 5d agoThreat actor in the wild 10 sources1

Context Engineering Inside the Harness: 4 Mechanisms That Beat Context Overflow and Goal Loss on Long-Horizon Tasks

Survey of four harness mechanisms—context budgeting, compaction, todo-state, and memory—that keep long-horizon LLM agents on task across 200+ tool calls.

The article details how agent harnesses, not larger context windows, solve context overflow and goal loss on long-horizon tasks, citing Chroma's Context Rot report showing 18 LLMs (GPT-4.1, Claude 4, Gemini 2.5, Qwen3) degrade on long inputs. Concrete implementations include LangChain Deep Agents offloading tool responses over 20,000 tokens to the filesystem and truncating old tool calls at 85% window usage, and Claude Code capping auto memory at 25KB while re-reading the 5 most recently modified files after compaction. OpenAI's Responses API now offers server-side compaction via context_management with a standalone /responses/compact endpoint, which Codex uses for long-running coding tasks. Manus reports a roughly 100:1 input-to-output token ratio per ~50-tool-call task, motivating todo.md state recitation to prevent goal drift.

MarkTechPost · 3d agoAI research1

Attackers Expose Ongoing AI Tool Use Targeting Organizations in Latin America

Unit 42 documents two AI-assisted intrusion campaigns against Latin American government, utility, and financial organizations using LLM-orchestrated tooling.

Palo Alto Networks Unit 42 tracks two ongoing intrusion clusters, CL-CRI-1131 (Mexican transportation, federal ministries, municipal water utilities) and CL-CRI-1163 (Brazilian financial sector), both using living-off-the-land techniques, SOCKS5 relays, and custom RATs. The attackers appear to orchestrate operations via commercial LLMs like Claude and GPT-4.1, evidenced by iterative batch scripts and AI-generated tunneling tool naming. The Mexican campaign (also reported as Operation Escaneo by CloudSEK) exfiltrated sensitive data via dynamic-DNS infrastructure with rotated multi-SAN TLS certificates between February and June 2026. This signals broader adoption of AI-enhanced operations by diverse threat groups in the region.

Palo Alto Unit 42 · 12d agoThreat actor in the wild1