CVE-2026-34451
MediumCVSS 5.4Exploitation Probability (EPSS)
Low risk27th percentile - higher than 27% of all known CVEs
Summary
Claude SDK for TypeScript versions 0.79.0 to before 0.81.0 contains a vulnerability in the local filesystem memory tool that validates model-supplied paths using a prefix check without appending a trailing path separator, allowing reads and writes outside the sandboxed memory directory.
Risk Assessment
A model steered by prompt injection can access files outside the intended memory directory, leading to data confidentiality and integrity breaches.
Recommendation
Update Claude SDK to version 0.81.0 or later.
Original NVD description (English source)
Claude SDK for TypeScript provides access to the Claude API from server-side TypeScript or JavaScript applications. From version 0.79.0 to before version 0.81.0, the local filesystem memory tool in the Anthropic TypeScript SDK validated model-supplied paths using a string prefix check that did not append a trailing path separator. A model steered by prompt injection could supply a crafted path that resolved to a sibling directory sharing the memory root's name as a prefix, allowing reads and writes outside the sandboxed memory directory. This issue has been patched in version 0.81.0.