CVE-2026-35352
A Time-of-Check to Time-of-Use (TOCTOU) race condition exists in the mkfifo utility of uutils coreutils. The utility creates a FIFO and then performs a path-based chmod to set permissions. A local attacker with write access to the parent directory can swap the newly created FIFO for a symbolic link between these two operations. This redirects the chmod call to an arbitrary file, potentially enabling privilege escalation if the utility is run with elevated privileges.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- Puntuación base: 7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.12%
- Percentil entre todas las CVEs puntuadas: 2
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
🎯 Técnicas ATT&CK
Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.
- Explotación
T1068Exploitation for Privilege Escalationprivilege escalation90 % - Impacto principal
T1548.004Elevated Execution with Promptprivilege escalation85 % - Impacto secundario
T1222.001Windows Permissionsdefense impairment80 %
TOCTOU en mkfifo con AV:L/PR:L permite escalar privilegios manipulando permisos de archivos arbitrarios entre las operaciones de creación y chmod.
Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.
🛡️ Mitigaciones ATT&CK que cubren estas técnicas
Tecnologías afectadas (1)
CWE
- CWE-367
Referencias
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-35352",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-35352",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "total"
}
],
"version": "2.0.3",
"timestamp": "2026-04-24T13:42:47.744415Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security@ubuntu.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7,
"attackVector": "LOCAL",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H",
"integrityImpact": "HIGH",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "HIGH"
},
"impactScore": 5.9,
"exploitabilityScore": 1
}
]
},
"affected": [
{
"source": "security@ubuntu.com",
"affectedData": [
{
"repo": "https://github.com/uutils/coreutils",
"vendor": "Uutils",
"product": "coreutils",
"platforms": [
"Linux",
"Unix",
"macOS"
],
"packageName": "coreutils",
"collectionURL": "https://github.com/uutils",
"defaultStatus": "affected"
}
]
}
],
"published": "2026-04-22T17:16:37.597",
"references": [
{
"url": "https://github.com/uutils/coreutils/issues/10020",
"tags": [
"Exploit",
"Issue Tracking",
"Vendor Advisory"
],
"source": "security@ubuntu.com"
},
{
"url": "http://www.openwall.com/lists/oss-security/2026/05/04/4",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://www.openwall.com/lists/oss-security/2026/05/04/5",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://www.openwall.com/lists/oss-security/2026/05/04/6",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://github.com/uutils/coreutils/issues/10020",
"tags": [
"Exploit",
"Issue Tracking",
"Vendor Advisory"
],
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "security@ubuntu.com",
"description": [
{
"lang": "en",
"value": "CWE-367"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "A Time-of-Check to Time-of-Use (TOCTOU) race condition exists in the mkfifo utility of uutils coreutils. The utility creates a FIFO and then performs a path-based chmod to set permissions. A local attacker with write access to the parent directory can swap the newly created FIFO for a symbolic link between these two operations. This redirects the chmod call to an arbitrary file, potentially enabling privilege escalation if the utility is run with elevated privileges."
}
],
"lastModified": "2026-06-17T10:40:26.690",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:uutils:coreutils:-:*:*:*:*:rust:*:*",
"vulnerable": true,
"matchCriteriaId": "4A9AF9E4-E17C-48AD-8051-B49998618839"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security@ubuntu.com"
}