Vulnerability-Lookup

GHSA-5474-4W2J-MQ4C

Vulnerability from github – Published: 2026-04-01 21:16 – Updated: 2026-04-24 20:59

Summary

Claude SDK for TypeScript: Memory Tool Path Validation Allows Sandbox Escape to Sibling Directories

Details

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.

Users on the affected versions are advised to update to the latest version.

Claude SDK for TypeScript thanks hackerone.com/nicksim for reporting this issue!

Severity

5.4 (Medium)


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

6.3 (Medium)


                  
                    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

Show details on source website

JSON

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{
  "affected": [
    {
      "package": {
        "ecosystem": "npm",
        "name": "@anthropic-ai/sdk"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.79.0"
            },
            {
              "fixed": "0.81.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34451"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-22",
      "CWE-41"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-01T21:16:49Z",
    "nvd_published_at": "2026-03-31T22:16:20Z",
    "severity": "MODERATE"
  },
  "details": "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\u0027s name as a prefix, allowing reads and writes outside the sandboxed memory directory.\n\nUsers on the affected versions are advised to update to the latest version.\n\nClaude SDK for TypeScript thanks [hackerone.com/nicksim](https://hackerone.com/nicksim) for reporting this issue!",
  "id": "GHSA-5474-4w2j-mq4c",
  "modified": "2026-04-24T20:59:12Z",
  "published": "2026-04-01T21:16:49Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/anthropics/anthropic-sdk-typescript/security/advisories/GHSA-5474-4w2j-mq4c"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34451"
    },
    {
      "type": "WEB",
      "url": "https://github.com/anthropics/anthropic-sdk-typescript/commit/0ac69b3438ee9c96b21a7d3c39c07b7cdb6995d9"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/anthropics/anthropic-sdk-typescript"
    },
    {
      "type": "WEB",
      "url": "https://github.com/anthropics/anthropic-sdk-typescript/releases/tag/sdk-v0.81.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "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",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Claude SDK for TypeScript: Memory Tool Path Validation Allows Sandbox Escape to Sibling Directories"
}

CVE-2026-34451 (GCVE-0-2026-34451)

Vulnerability from cvelistv5 – Published: 2026-03-31 21:35 – Updated: 2026-04-01 18:57

Title

Claude SDK for TypeScript: Memory Tool Path Validation Allows Sandbox Escape to Sibling Directories

Summary

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.

Severity

6.3 (Medium)


                        
                          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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-01 18:56 UTC

CWE

CWE-22 - Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')
CWE-41 - Improper Resolution of Path Equivalence

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/anthropics/anthropic-sdk-types…	x_refsource_CONFIRM
https://github.com/anthropics/anthropic-sdk-types…	x_refsource_MISC
https://github.com/anthropics/anthropic-sdk-types…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
anthropics	anthropic-sdk-typescript	Affected: >= 0.79.0, < 0.81.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-34451",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-04-01T18:56:48.666585Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-04-01T18:57:05.442Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "anthropic-sdk-typescript",
          "vendor": "anthropics",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 0.79.0, \u003c 0.81.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "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\u0027s name as a prefix, allowing reads and writes outside the sandboxed memory directory. This issue has been patched in version 0.81.0."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "HIGH",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "LOW",
            "vulnIntegrityImpact": "LOW"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-22",
              "description": "CWE-22: Improper Limitation of a Pathname to a Restricted Directory (\u0027Path Traversal\u0027)",
              "lang": "en",
              "type": "CWE"
            }
          ]
        },
        {
          "descriptions": [
            {
              "cweId": "CWE-41",
              "description": "CWE-41: Improper Resolution of Path Equivalence",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-03-31T21:35:21.018Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/anthropics/anthropic-sdk-typescript/security/advisories/GHSA-5474-4w2j-mq4c",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/anthropics/anthropic-sdk-typescript/security/advisories/GHSA-5474-4w2j-mq4c"
        },
        {
          "name": "https://github.com/anthropics/anthropic-sdk-typescript/commit/0ac69b3438ee9c96b21a7d3c39c07b7cdb6995d9",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/anthropics/anthropic-sdk-typescript/commit/0ac69b3438ee9c96b21a7d3c39c07b7cdb6995d9"
        },
        {
          "name": "https://github.com/anthropics/anthropic-sdk-typescript/releases/tag/sdk-v0.81.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/anthropics/anthropic-sdk-typescript/releases/tag/sdk-v0.81.0"
        }
      ],
      "source": {
        "advisory": "GHSA-5474-4w2j-mq4c",
        "discovery": "UNKNOWN"
      },
      "title": "Claude SDK for TypeScript: Memory Tool Path Validation Allows Sandbox Escape to Sibling Directories"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-34451",
    "datePublished": "2026-03-31T21:35:21.018Z",
    "dateReserved": "2026-03-27T18:18:14.895Z",
    "dateUpdated": "2026-04-01T18:57:05.442Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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GHSA-5474-4W2J-MQ4C

CVE-2026-34451 (GCVE-0-2026-34451)

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