{"data":{"id":"491f8f23-75ed-4c3d-bec6-3033d69d785c","title":"Claude Code has an MCP security problem — and your developers are already using it","summary":"Claude Code, Anthropic's AI coding assistant, stores OAuth tokens (security credentials that prove access permission) in plaintext in a configuration file, and researchers discovered an attack where malicious npm packages (JavaScript libraries) can silently redirect these tokens to attacker-controlled servers before they reach legitimate services like GitHub or Jira. The attack is difficult to detect because the requests appear legitimate in audit logs, and Anthropic has not released a patch despite knowing about the vulnerability since April.","solution":"N/A -- no mitigation discussed in source.","labels":["security"],"sourceUrl":"https://www.csoonline.com/article/4181230/claude-code-has-an-mcp-security-problem-and-your-developers-are-already-using-it.html","publishedAt":"2026-06-05T09:00:00.000Z","cveId":null,"cweIds":null,"cvssScore":null,"cvssSeverity":null,"severity":"high","attackType":["supply_chain","rag_poisoning"],"issueType":"news","affectedPackages":null,"affectedVendors":["Anthropic"],"affectedVendorsRaw":["Anthropic","Claude Code","Model Context Protocol","Jira","Confluence","GitHub"],"classifierModel":"claude-haiku-4-5-20251001","classifierPromptVersion":"v3","cvssVector":null,"attackVector":null,"attackComplexity":null,"privilegesRequired":null,"userInteraction":null,"exploitMaturity":null,"epssScore":null,"patchAvailable":null,"disclosureDate":"2026-06-05T09:00:00.000Z","capecIds":null,"crossRefCount":0,"attackSophistication":"moderate","impactType":["confidentiality","integrity"],"aiComponentTargeted":"api","llmSpecific":true,"classifierConfidence":0.92,"researchCategory":null,"atlasIds":null}}