{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-35355", "assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc", "state": "PUBLISHED", "assignerShortName": "canonical", "dateReserved": "2026-04-02T12:58:56.087Z", "datePublished": "2026-04-22T16:08:14.960Z", "dateUpdated": "2026-04-22T18:01:47.122Z"}, "containers": {"cna": {"title": "uutils coreutils install Arbitrary File Overwrite via Symlink TOCTOU Race", "affected": [{"vendor": "Uutils", "product": "coreutils", "platforms": ["Linux", "Unix", "macOS"], "collectionURL": "https://github.com/uutils", "packageName": "coreutils", "repo": "https://github.com/uutils/coreutils", "versions": [{"status": "affected", "lessThan": "0.6.0", "version": "0", "versionType": "semver"}], "defaultStatus": "unaffected"}], "problemTypes": [{"descriptions": [{"lang": "en", "cweId": "CWE-367", "description": "CWE-367: Time-of-Check Time-of-Use (TOCTOU) Race Condition", "type": "CWE"}]}], "impacts": [{"capecId": "CAPEC-29", "descriptions": [{"lang": "en", "value": "CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions"}]}], "descriptions": [{"lang": "en", "value": "The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files."}], "references": [{"url": "https://github.com/uutils/coreutils/pull/10067", "tags": ["issue-tracking", "patch"]}, {"url": "https://github.com/uutils/coreutils/releases/tag/0.6.0", "tags": ["vendor-advisory"]}], "metrics": [{"format": "CVSS", "scenarios": [{"lang": "en", "value": "GENERAL"}], "cvssV3_1": {"version": "3.1", "attackVector": "LOCAL", "attackComplexity": "HIGH", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "availabilityImpact": "HIGH", "baseSeverity": "MEDIUM", "baseScore": 6.3, "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H"}}], "credits": [{"lang": "en", "value": "Zellic", "type": "finder"}], "source": {"discovery": "EXTERNAL"}, "providerMetadata": {"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc", "shortName": "canonical", "dateUpdated": "2026-04-22T16:08:14.960Z"}}, "adp": [{"references": [{"url": "https://github.com/uutils/coreutils/pull/10067", "tags": ["exploit"]}], "metrics": [{"other": {"type": "ssvc", "content": {"timestamp": "2026-04-22T18:01:44.426332Z", "id": "CVE-2026-35355", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "role": "CISA Coordinator", "version": "2.0.3"}}}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-22T18:01:47.122Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-35355", "role": "CISA Coordinator", "options": [{"Exploitation": "poc"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-04-22T18:01:44.426332Z"}}}], "references": [{"url": "https://github.com/uutils/coreutils/pull/10067", "tags": ["exploit"]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-04-22T18:01:21.419Z"}}], "cna": {"title": "uutils coreutils install Arbitrary File Overwrite via Symlink TOCTOU Race", "source": {"discovery": "EXTERNAL"}, "credits": [{"lang": "en", "type": "finder", "value": "Zellic"}], "impacts": [{"capecId": "CAPEC-29", "descriptions": [{"lang": "en", "value": "CAPEC-29: Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions"}]}], "metrics": [{"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 6.3, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H", "integrityImpact": "HIGH", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "scenarios": [{"lang": "en", "value": "GENERAL"}]}], "affected": [{"repo": "https://github.com/uutils/coreutils", "vendor": "Uutils", "product": "coreutils", "versions": [{"status": "affected", "version": "0", "lessThan": "0.6.0", "versionType": "semver"}], "platforms": ["Linux", "Unix", "macOS"], "packageName": "coreutils", "collectionURL": "https://github.com/uutils", "defaultStatus": "unaffected"}], "references": [{"url": "https://github.com/uutils/coreutils/pull/10067", "tags": ["issue-tracking", "patch"]}, {"url": "https://github.com/uutils/coreutils/releases/tag/0.6.0", "tags": ["vendor-advisory"]}], "descriptions": [{"lang": "en", "value": "The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files."}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-367", "description": "CWE-367: Time-of-Check Time-of-Use (TOCTOU) Race Condition"}]}], "providerMetadata": {"orgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc", "shortName": "canonical", "dateUpdated": "2026-04-22T16:08:14.960Z"}}}, "cveMetadata": {"cveId": "CVE-2026-35355", "state": "PUBLISHED", "dateUpdated": "2026-04-22T18:01:47.122Z", "dateReserved": "2026-04-02T12:58:56.087Z", "assignerOrgId": "cc1ad9ee-3454-478d-9317-d3e869d708bc", "datePublished": "2026-04-22T16:08:14.960Z", "assignerShortName": "canonical"}, "dataVersion": "5.2"}

{"cveTags": [], "descriptions": [{"lang": "en", "value": "The install utility in uutils coreutils is vulnerable to a Time-of-Check to Time-of-Use (TOCTOU) race condition during file installation. The implementation unlinks an existing destination file and then recreates it using a path-based operation without the O_EXCL flag. A local attacker can exploit the window between the unlink and the subsequent creation to swap the path with a symbolic link, allowing them to redirect privileged writes to overwrite arbitrary system files."}], "id": "CVE-2026-35355", "lastModified": "2026-04-22T21:23:52.620", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 6.3, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "HIGH", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H", "version": "3.1"}, "exploitabilityScore": 1.0, "impactScore": 5.2, "source": "security@ubuntu.com", "type": "Secondary"}]}, "published": "2026-04-22T17:16:37.993", "references": [{"source": "security@ubuntu.com", "url": "https://github.com/uutils/coreutils/pull/10067"}, {"source": "security@ubuntu.com", "url": "https://github.com/uutils/coreutils/releases/tag/0.6.0"}, {"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "url": "https://github.com/uutils/coreutils/pull/10067"}], "sourceIdentifier": "security@ubuntu.com", "vulnStatus": "Awaiting Analysis", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-367"}], "source": "security@ubuntu.com", "type": "Secondary"}]}

{}

{"analysis": {"en": {"generated_at": "2026-04-22T18:12:12.349847+00:00", "value": {"mitigation_remediation": ["Upgrade to uutils coreutils version 0.6.0 or later, where the race condition has been fixed.", "If upgrading is not immediately possible, restrict write permissions on installation targets and disallow symlink creation for unprivileged users.", "Audit the system for unexpected symbolic links in install directories and monitor for anomalous file modifications in critical paths."], "summary": {"action": "Immediate Patch", "impact": "Arbitrary file overwrite via symlink TOCTOU race"}, "threat_synthesis": {"affected_systems": "The affected product is uutils coreutils. No specific affected release version is listed in the CVE data, so all versions prior to the fix should be considered vulnerable.", "description_and_impact": "The install utility in uutils coreutils implements a two\u2011step file creation, first unlinking an existing destination and then creating the new file without the O_EXCL flag. The time gap between unlinking and recreating the file allows a local attacker to create a symbolic link that redirects the write operation to an arbitrary system file. The result is that privileged writes can be redirected to overwrite existing files, compromising the integrity of the affected system. This flaw is a classic Time\u2011of\u2011Check to Time\u2011of\u2011Use (CWE\u2011367) weakness.", "risk_and_exploitability": "The CVSS score of 6.3 indicates a moderate severity. The EPSS score is not available, and the vulnerability is not listed in the CISA KEV catalog, suggesting no known active exploitation in the wild. The attack vector is local; a user with write access to the installation paths can target the race condition. No remote exploitation path is documented in the provided description."}}}}, "created": "2026-04-22T18:15:15.484568+00:00", "updated": "2026-04-22T18:15:15.484579+00:00", "vendors": []}