Forever Security breaks out of the built-in browsers of five AI coding assistants, with Codex and VS Code unpatched
Help Net Security reports Forever Security "found ways out of the built-in browsers" in Cursor, GitHub Copilot, OpenAI's Codex, Microsoft's VS Code and Anthropic's Claude Desktop; on its own machine "the sweep collected SSH keys, .env files, npm tokens and the hosts file, then sent them out." Cursor patched on October 1 and Copilot 1.1.29 fixed its bug on October 13; Anthropic and Microsoft declined the reports citing Workspace Trust, and Codex and VS Code had no fix as of October 29.
A trojanized build of the Claude Code extension planted an attacker SSH key on developer machines for about 11 hours
StepSecurity says version 2.1.313 of the Claude Code extension was published to Open VSX carrying a malicious loader that "planted an attacker SSH key, installed per-OS persistence, opened a reverse SSH tunnel" between 09:27 and 20:35 UTC on October 29, and that Cursor, whose marketplace mirrored it, reports at most 5,000 of its users received it. The malicious version was not developed or released by Anthropic, and how it reached the registry has not been publicly established.
Check Point says a campaign pairs genuine signed ChatGPT and Claude installers with a malicious DLL to drop a miner
CSO Online reports Check Point Research's account of Yoba, which uses fake GitHub repositories and websites boosted by SEO poisoning to deliver archives in which "a genuine signed Setup.exe from OpenAI or Anthropic is placed alongside a malicious file named winmm.dll", loaded by the executable; the observed final payload is the XMRig cryptocurrency miner. An earlier variant observed in June used a fake Cursor coding-agent application.
An infostealer now targets the saved sessions and keys of AI coding tools
Infosecurity Magazine reports Symantec's account of the Aoki infostealer, which targets locally stored credentials and sessions for Claude, ChatGPT, Codex, Cursor, Copilot, Gemini, JetBrains AI and Kiro, and quotes Symantec: "Like card data, a stolen AI key can be cashed in directly."
A compromised npm SDK harvests Claude, Cursor and MCP configuration files, then republishes itself under the victim's own publishing identity
Researchers reported that version 0.5.144 of the npm package tensorlake — described by The Hacker News as “a TypeScript software development kit (SDK) for Tensorlake applications, sandboxes, and cloud services” — was published with what Socket describes as “obfuscated malware that harvests credentials, exfiltrates secrets, establishes persistence.” The chain runs from a preinstall hook to package/lib/setup.mjs, an obfuscated loader, and a main payload at package/lib/Math_Symbol.js executed under the Bun runtime. What it takes includes npm and GitHub tokens, AWS credentials, HashiCorp Vault and Kubernetes credentials, SSH keys, .env files, cryptocurrency wallets and messaging-app data, and — the part specific to this target — the configuration and MCP files for Claude, Cursor, Kiro, Windsurf and Zed; it also drops the HackBrowserData binary. Exfiltration goes first to an endpoint at iseekaigogo[.]com, and on failure the malware reads an Ethereum contract to find a command-and-control address, with GitHub as a further fallback where encrypted data is staged in a public repository. A PowerShell “hostage token” monitor polls the GitHub API with the stolen token and, if the token is revoked, runs an attacker-supplied handler that wipes the home directory. It spreads on its own: Socket says “the worm enumerates packages associated with the victim's publishing identity,” builds Sigstore provenance and republishes compromised versions, and StepSecurity reports that it “writes .claude/settings.json and .vscode/tasks.json files into repos it can reach” so that it runs again when the project is next opened in Claude Code or VS Code. On timing, the first rogue commit to the main branch of tensorlakeai/tensorlake was made at 01:20 UTC on October 7, 2026 under a maintainer's name, and the release workflow published 0.5.144 to npm about a day later; the version has since been removed from the registry. The activity is attributed to the ChainDrop / Shai-Hulud campaign, first documented in early August 2026, which compromised hundreds of npm packages including Keyv and Cacheable. No download count for the malicious version was published.
AIUC raises $40 million to extend its agent audits, standards and insurance to frontier models
The Artificial Intelligence Underwriting Company raised a $40 million Series A led by Ribbit Capital, with First Harmonic and Terrain participating, and says it will “extend our audits, standards and insurance from agents to frontier models.” Its AIUC-1 certification is held by Cursor, ElevenLabs, Harvey, KPMG, Lovable, UiPath and Fin, and the company says ElevenLabs obtained AI agent insurance backed by it.
A repository's own git config makes seven AI coding agents run attacker code before any prompt
Manifold Security reports eight findings across seven AI coding agents in which a repository's git configuration names a command that git then executes on the host, with the user's privileges, before any trust prompt, because agents run git commands at session start to gather context. The named vector is the core.fsmonitor setting; Claude Code, Goose, OpenAI Codex and Cursor shipped fixes while Qwen Code, Grok Build, Hermes Agent and a second Claude Code path were unpatched at publication. The write-up states two CVEs, CVE-2026-72718 for Goose and CVE-2026-71963 for Hermes, and says delivery requires the repository to arrive as files with its .git directory intact rather than through a clone.
Ransomware operators ran Cursor Agent inside victim networks to carry out hands-on intrusion steps
Gambit Security reports that operators of the Aurora ransomware operation used Cursor Agent, running Claude Sonnet, for hands-on exploitation across ten target organisations between April 8 and May 21, 2026, tasking it with VPN and proxy setup, Nmap and NetExec scanning, domain enumeration, NTLM relay using PetitPotam and Impacket, and Certipy certificate attacks. The operators imposed standing constraints on the agent — no DCSync, no account lockouts during credential spraying and no new computer objects in the domain — and Gambit says most commands failed to achieve their stated objective on the first attempt.
Cisco Talos analyses prompt logs recovered from threat actors' own machines
Talos examined a corpus of prompt logs left by Claude Code, CodeX, Cursor and Gemini on threat actor endpoints, grouping the use into AI as a malicious software engineer, AI for scaling criminal operations and AI for vulnerability research. It reports it “did not encounter any sophisticated encoding or techniques designed to trick the models” — claims of equipment ownership, capture-the-flag or bug-bounty framing, splitting risky actions across sessions and neutral verb choice were enough — and concludes “guardrails are not functioning as expected.”
npm worm in keyv and cacheable namespaces steals AI coding-tool credentials and persists via Claude Code and VS Code hooks
A self-propagating npm supply-chain compromise spread from the keyv and cacheable namespaces into over 400 packages, using a preinstall script to harvest cloud credentials, CI/CD secrets, private keys and cryptocurrency wallets, and republishing poisoned versions through npm OIDC trusted publishing. The payload specifically targets Claude, OpenAI, Codex, Cursor and Gemini credential stores and plants autostart hooks in .claude/settings.json and .vscode/tasks.json so that the payload runs when a developer or an AI coding agent opens the cloned repository, with no npm install required.
Black Hat USA 2026 vendor announcements centre on AI agent runtime protection, discovery and least-privilege enforcement
SecurityWeek's three-part roundup of Black Hat USA 2026 announcements documents a concentrated wave of defensive products aimed at securing AI agents, including Cyera Agent Guardian and Menlo Security MARS for prompt-injection and exfiltration protection, KnowBe4 Agent Risk Manager and Mimecast Agent Risk Center for agent discovery and behaviour monitoring, Varonis intent-based access control and Zero Networks least-agency enforcement for constraining agent permissions, and Acalvio Deception Guardrails for honeytokens targeting agentic environments. Legit Security's VibeGuard 2.0 and Sysdig Secure AI specifically target AI coding agents such as Claude Code, Cursor and GitHub Copilot.
Pillar Security reports sandbox escapes in four AI coding agents, triggered by content inside a repository
Pillar Security published seven sandbox escapes across four AI coding agents — three in Cursor, one in OpenAI's Codex CLI, one in Google's Gemini CLI and two in Google's Antigravity — in which the agent stays inside its sandbox and writes a file that a trusted tool outside the sandbox later runs, loads or scans. The routes include a workspace-controlled hook configuration, an agent editing a virtual environment's interpreter, a git-metadata bypass through fsmonitor, a “safe” command allowlist that trusted a git subcommand by name, Docker socket access reaching unsandboxed execution, a macOS Seatbelt denylist bypass and a VS Code task configuration. Pillar says the trigger is prompt injection planted in a README, an issue, a dependency or a diff, and that “an agent's blast radius is not the agent process; it includes everything the agent can write that the host later trusts.”