{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "0"
              },
              {
                "fixed": "2.1.129"
              }
            ],
            "source": "AFFECTED_FIELD"
          },
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "5c0e4f96eba18665ad14f3097a670334d8e8427e"
            }
          ],
          "repo": "https://github.com/anthropics/claude-code",
          "type": "GIT"
        }
      ]
    }
  ],
  "aliases": [
    "GHSA-5j29-h97v-84ch"
  ],
  "database_specific": {
    "cna_assigner": "Anthropic",
    "cwe_ids": [
      "CWE-22",
      "CWE-367",
      "CWE-61"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103435.json"
  },
  "details": "Claude Code validated that a target file path resided within the project working directory at permission-check time, but re-resolved the path at write time without repeating that validation. This time-of-check to time-of-use (TOCTOU) gap allowed an attacker who could write to the workspace to atomically replace a project file with a symlink, causing Claude Code to follow the symlink and write its output to an arbitrary file outside the project sandbox. Exploitation required the ability to win a race condition against the write operation and write access to the shared workspace, enabling a lower-privileged attacker to redirect benign edits to sensitive files (e.g., shell configuration) in a higher-privileged session.\n\nUsers on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.\n\nThank you to hackerone.com/c_h4ck_0 for reporting this issue.",
  "id": "CVE-2026-103435",
  "modified": "2026-10-09T02:30:32.690613864Z",
  "published": "2026-10-07T12:50:02.572Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/103xxx/CVE-2026-103435.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/anthropics/claude-code/security/advisories/GHSA-5j29-h97v-84ch"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-103435"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Arbitrary File Write via Write-Time Symlink Following (TOCTOU) in Claude Code"
}