How severe is CVE-2026-34451?

CVE-2026-34451 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2026-34451 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-34451?

CVE-2026-34451 affects Anthropic Claude Sdk For Typescript. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-34451?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-34451 have an EU (EUVD) identifier?

Yes. CVE-2026-34451 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17679.

When was CVE-2026-34451 published?

CVE-2026-34451 was published on 2026-03-31 and last updated on 2026-06-17.

CVE-2026-34451

CVE-2026-34451 is a medium-severity vulnerability in Anthropic Claude Sdk For Typescript with a CVSS 3.x base score of 5.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-22.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
CVSS v4: 6.3
EPSS exploit prediction: 0% (21st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-17679
Weakness: CWE-22
Affected product: Anthropic Claude Sdk For Typescript
Published: 2026-03-31
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2026-34451?: 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.
How severe is CVE-2026-34451?: CVE-2026-34451 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2026-34451 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-34451?: CVE-2026-34451 affects Anthropic Claude Sdk For Typescript. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-34451?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-34451 have an EU (EUVD) identifier?: Yes. CVE-2026-34451 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-17679.
When was CVE-2026-34451 published?: CVE-2026-34451 was published on 2026-03-31 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:anthropic:claude_sdk_for_typescript:*:*:*:*:*:*:*:*

More vulnerabilities in Anthropic Claude Sdk For Typescript

CVE-2026-41686 — Medium (CVSS 4.4): Claude SDK for TypeScript provides access to the Claude API from server-side TypeScript or JavaScript applications.…

All CVEs affecting Anthropic Claude Sdk For Typescript →

Other CWE-22 (Path Traversal) vulnerabilities

CVE-2026-48282 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Limitation of a Pathname to a Restricted…
CVE-2026-54917 — Critical (CVSS 10.0): SeaweedFS is a distributed storage system for object storage (S3), file systems, and Iceberg tables. Prior to 4.30, the…
CVE-2026-11429 — Critical (CVSS 10.0): Two endpoints in the Vault Service ScriptsController, shared by Altium Enterprise Server and Altium 365, accept file…
CVE-2026-34909 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit a Path Traversal vulnerability found in UniFi OS devices to…
CVE-2026-7411 — Critical (CVSS 10.0): In Eclipse BaSyx Java Server SDK versions prior to 2.0.0-milestone-10, inadequate path normalization in the Submodel…
CVE-2026-36767 — Critical (CVSS 10.0): A path traversal vulnerability in the /content/images/add endpoint of shopizer v3.2.5 allows attackers write arbitrary…

Browse all CWE-22 (Path Traversal) vulnerabilities →