CVE-2026-103435

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{"affected": [{"affectedData": [{"product": "@anthropic-ai/claude-code", "vendor": "Anthropic", "versions": [{"lessThan": "2.1.129", "status": "affected", "version": "0", "versionType": "semver"}]}], "source": "98a01053-8a31-4f6d-9aa9-252be161adc6"}], "cveTags": [], "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."}], "id": "CVE-2026-103435", "lastModified": "2026-10-07T15:16:57.037", "metrics": {"cvssMetricV40": [{"cvssData": {"Automatable": "NOT_DEFINED", "Recovery": "NOT_DEFINED", "Safety": "NOT_DEFINED", "attackComplexity": "LOW", "attackRequirements": "PRESENT", "attackVector": "NETWORK", "availabilityRequirement": "NOT_DEFINED", "baseScore": 7.7, "baseSeverity": "HIGH", "confidentialityRequirement": "NOT_DEFINED", "exploitMaturity": "NOT_DEFINED", "integrityRequirement": "NOT_DEFINED", "modifiedAttackComplexity": "NOT_DEFINED", "modifiedAttackRequirements": "NOT_DEFINED", "modifiedAttackVector": "NOT_DEFINED", "modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedUserInteraction": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "privilegesRequired": "NONE", "providerUrgency": "NOT_DEFINED", "subAvailabilityImpact": "NONE", "subConfidentialityImpact": "NONE", "subIntegrityImpact": "NONE", "userInteraction": "PASSIVE", "valueDensity": "NOT_DEFINED", "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X", "version": "4.0", "vulnAvailabilityImpact": "HIGH", "vulnConfidentialityImpact": "HIGH", "vulnIntegrityImpact": "HIGH", "vulnerabilityResponseEffort": "NOT_DEFINED"}, "source": "98a01053-8a31-4f6d-9aa9-252be161adc6", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-103435", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "total"}], "role": "CISA Coordinator", "timestamp": "2026-10-07T14:39:02.916533Z", "version": "2.0.3"}}]}, "published": "2026-10-07T13:17:16.690", "references": [{"source": "98a01053-8a31-4f6d-9aa9-252be161adc6", "url": "https://github.com/anthropics/claude-code/security/advisories/GHSA-5j29-h97v-84ch"}], "sourceIdentifier": "98a01053-8a31-4f6d-9aa9-252be161adc6", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-22"}, {"lang": "en", "value": "CWE-61"}, {"lang": "en", "value": "CWE-367"}], "source": "98a01053-8a31-4f6d-9aa9-252be161adc6", "type": "Secondary"}]}

{"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"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "[0,2.1.129)"}}], "enrichment": {"confidence": 100.0, "confidence_source": "manual", "scores": [{"score": 100.0, "source": "manual"}]}, "original": {"product": "@anthropic-ai/claude-code", "source": "cna", "vendor": "Anthropic"}, "product": "claude_code", "vendor": "anthropic"}], "created": "2026-10-07T15:15:18.200989+00:00", "updated": "2026-10-09T08:16:03.666460+00:00", "vendors": ["anthropic", "anthropic$PRODUCT$claude_code"]}