Polymarket Pays Out $3.9 Million After DebugBear Third-Party Script Compromise

Malicious Claude Code Update 2.1.313 Distributed via Cursor Marketplace Infects Up to 5,000 Users

Security researchers at OpenSourceMalware discovered a trojanized version of the official Claude Code extension from Anthropic that was pushed as a legitimate update through the Cursor IDE marketplace. The malicious package, version 2.1.313, inserted a 66-line loader that added an attacker-controlled SSH key named svc-telemetry to ~/.ssh/authorized_keys, established a reverse tunnel to 134.209.82.225, deployed persistence mechanisms, and exfiltrated host metadata including IP address, hostname, username, OS details, Git email, and names of environment variables containing KEY, TOKEN, SECRET, PASS, AWS, or GCP. The campaign ran for roughly eleven hours on 29 October 2026 and was limited exclusively to the Cursor marketplace; no malicious versions appeared in Open VSX or the Microsoft VS Code Marketplace. Cursor responded by removing the package, rebuilding the marketplace, rotating keys, and disabling the attacker-controlled server at 134.209.82.225:8099. The company stated that at most 5,000 users installed the compromised update and committed to direct outreach while recommending isolation, SSH key removal, persistence cleanup, and credential rotation. The incident highlights supply-chain risks associated with automatic extension updates and the difficulty of detecting tampering when a legitimate publisher’s name and signing appear intact.

Malicious Claude Code Extension with SSH Backdoor Found in Cursor Marketplace Affecting Up to 5000 Users

A malicious version of the Claude Code extension was discovered in the Cursor extension catalog on October 29. The package, version 2.1.313, remained available for approximately 11 hours and could have impacted up to 5000 users. It was not developed by Anthropic and instead collected system information including IP addresses and Git email settings before installing an attacker-controlled SSH key. The extension attempted to establish remote access with persistence mechanisms, though some installations failed due to missing administrative privileges. Cursor responded by removing the package, auditing other extensions, and disabling the attackers' server. Users are advised to fully clean up residual scripts and rotate credentials from a trusted device rather than simply uninstalling the extension.

Passwordless Kubernetes Image Pulling with Artifact Keeper via ServiceAccount Tokens

Kubernetes 1.34 and later enables kubelet to forward a pod's ServiceAccount token to an external image credential provider plugin, allowing the plugin to exchange it for short-lived read-only credentials from a compatible registry. Artifact Keeper, an open-source Rust-based OCI and package registry, implements an OIDC provider that validates these tokens and issues temporary credentials without requiring imagePullSecrets in manifests. The approach follows zero-trust principles by eliminating long-lived secrets that can leak across namespaces or clusters. A custom credential provider binary handles the token exchange, enforces audience restrictions, and redacts sensitive data from logs. The solution requires specific ClusterRole permissions for nodes, kubelet flags, and registry-side OIDC mappings that bind Kubernetes namespaces to read-only groups. Testing on kind 1.34.3 confirmed successful pulls for authorized ServiceAccounts and clear 401 errors for unauthorized ones when imagePullPolicy is set to Always.