CVE-2026-34451

medium

Description

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.

References

https://github.com/anthropics/anthropic-sdk-typescript/security/advisories/GHSA-5474-4w2j-mq4c

https://github.com/anthropics/anthropic-sdk-typescript/releases/tag/sdk-v0.81.0

https://github.com/anthropics/anthropic-sdk-typescript/commit/0ac69b3438ee9c96b21a7d3c39c07b7cdb6995d9

Details

Source: Mitre, NVD

Published: 2026-03-31

Updated: 2026-04-20

Risk Information

CVSS v2

Base Score: 4

Vector: CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N

Severity: Medium

CVSS v3

Base Score: 5.4

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N

Severity: Medium

CVSS v4

Base Score: 6.3

Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

Severity: Medium

EPSS

EPSS: 0.00044