{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-103435", "assignerOrgId": "98a01053-8a31-4f6d-9aa9-252be161adc6", "state": "PUBLISHED", "assignerShortName": "Anthropic", "dateReserved": "2026-09-30T15:35:18.777Z", "datePublished": "2026-10-07T12:50:02.572Z", "dateUpdated": "2026-10-07T14:39:13.225Z"}, "containers": {"cna": {"descriptions": [{"lang": "en", "value": "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."}], "affected": [{"vendor": "Anthropic", "product": "@anthropic-ai/claude-code", "versions": [{"version": "0", "lessThan": "2.1.129", "status": "affected", "versionType": "semver"}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-22", "description": "CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')"}]}, {"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-61", "description": "CWE-61 UNIX Symbolic Link (Symlink) Following"}]}, {"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-367", "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition"}]}], "references": [{"url": "https://github.com/anthropics/claude-code/security/advisories/GHSA-5j29-h97v-84ch"}], "metrics": [{"cvssV4_0": {"version": "4.0", "vectorString": "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", "baseScore": 7.7, "baseSeverity": "HIGH"}}], "title": "Arbitrary File Write via Write-Time Symlink Following (TOCTOU) in Claude Code", "providerMetadata": {"orgId": "98a01053-8a31-4f6d-9aa9-252be161adc6", "shortName": "Anthropic", "dateUpdated": "2026-10-07T12:50:02.572Z"}}, "adp": [{"metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-10-07T14:39:02.916533Z", "id": "CVE-2026-103435", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "total"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-07T14:39:13.225Z"}}]}}

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{"bugzilla": {"description": "claude-code: claude-code: Arbitrary file write via TOCTOU race condition", "id": "2547427", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2547427"}, "csaw": false, "cvss3": {"cvss3_base_score": "7.0", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-367", "details": ["A flaw was found in claude-code. An attacker with write access to a shared workspace can achieve arbitrary file modification and privilege escalation by exploiting a time-of-check to time-of-use (TOCTOU) race condition. By replacing a project file with a symbolic link between the permission check and the write operation, an attacker can bypass workspace restrictions and overwrite sensitive files outside the project sandbox."], "name": "CVE-2026-103435", "package_state": [{"cpe": "cpe:/a:redhat:openshift_devspaces:3", "fix_state": "Affected", "package_name": "devspaces/pluginregistry-rhel9", "product_name": "Red Hat OpenShift Dev Spaces"}], "public_date": "2026-10-07T12:50:02Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-103435\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-103435\nhttps://github.com/anthropics/claude-code/security/advisories/GHSA-5j29-h97v-84ch"], "threat_severity": "Moderate"}