CVE-2018-20482
Estado: ModificadaMedia (4.7)—
GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed to be archived by a different user's process (e.g., a system backup running as root).
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 4.7
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.53%
- Percentil entre todas las CVEs puntuadas: 43
- Fecha de la puntuación: 5/10/2026
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).
Tecnologías afectadas (3)
CWE
- CWE-835
Referencias
- http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454
- http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html
- http://www.securityfocus.com/bid/106354
- https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html
- https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html
- https://news.ycombinator.com/item?id=18745431
- https://security.gentoo.org/glsa/201903-05
- https://twitter.com/thatcks/status/1076166645708668928
- https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug
- http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454
- http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html
- http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html
- http://www.securityfocus.com/bid/106354
- https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html
- https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html
- https://news.ycombinator.com/item?id=18745431
- https://security.gentoo.org/glsa/201903-05
- https://twitter.com/thatcks/status/1076166645708668928
- https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug
JSON original (NVD)
Mostrar
{
"id": "CVE-2018-20482",
"cveTags": [],
"metrics": {
"cvssMetricV2": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"version": "2.0",
"baseScore": 1.9,
"accessVector": "LOCAL",
"vectorString": "AV:L/AC:M/Au:N/C:N/I:N/A:P",
"authentication": "NONE",
"integrityImpact": "NONE",
"accessComplexity": "MEDIUM",
"availabilityImpact": "PARTIAL",
"confidentialityImpact": "NONE"
},
"acInsufInfo": false,
"impactScore": 2.9,
"baseSeverity": "LOW",
"obtainAllPrivilege": false,
"exploitabilityScore": 3.4,
"obtainUserPrivilege": false,
"obtainOtherPrivilege": false,
"userInteractionRequired": false
}
],
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 4.7,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "HIGH",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 1
}
]
},
"affected": [
{
"source": "cve@mitre.org",
"affectedData": [
{
"vendor": "n/a",
"product": "n/a",
"versions": [
{
"status": "affected",
"version": "n/a"
}
]
}
]
}
],
"published": "2018-12-26T18:29:00.373",
"references": [
{
"url": "http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html",
"tags": [
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://www.securityfocus.com/bid/106354",
"tags": [
"Third Party Advisory",
"VDB Entry"
],
"source": "cve@mitre.org"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://news.ycombinator.com/item?id=18745431",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://security.gentoo.org/glsa/201903-05",
"tags": [
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://twitter.com/thatcks/status/1076166645708668928",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "cve@mitre.org"
},
{
"url": "http://git.savannah.gnu.org/cgit/tar.git/commit/?id=c15c42ccd1e2377945fd0414eca1a49294bff454",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://lists.gnu.org/archive/html/bug-tar/2018-12/msg00023.html",
"tags": [
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://lists.opensuse.org/opensuse-security-announce/2019-04/msg00077.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "http://www.securityfocus.com/bid/106354",
"tags": [
"Third Party Advisory",
"VDB Entry"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2018/12/msg00023.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.debian.org/debian-lts-announce/2021/11/msg00025.html",
"tags": [
"Mailing List",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://news.ycombinator.com/item?id=18745431",
"tags": [
"Exploit",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://security.gentoo.org/glsa/201903-05",
"tags": [
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://twitter.com/thatcks/status/1076166645708668928",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://utcc.utoronto.ca/~cks/space/blog/sysadmin/TarFindingTruncateBug",
"tags": [
"Patch",
"Third Party Advisory"
],
"source": "af854a3a-2127-422b-91ae-364da2661108"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "CWE-835"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "GNU Tar through 1.30, when --sparse is used, mishandles file shrinkage during read access, which allows local users to cause a denial of service (infinite read loop in sparse_dump_region in sparse.c) by modifying a file that is supposed to be archived by a different user's process (e.g., a system backup running as root)."
},
{
"lang": "es",
"value": "GNU Tar, hasta la versión 1.30, cuando se emplea --sparse, gestiona de manera incorrecta el encogimiento de archivos durante el acceso de lectura, lo que permite que usuarios locales provoquen una denegación de servicio (bucle infinito de lectura en sparse_dump_region en sparse.c) modificando un archivo que debería ser archivado por el proceso de un usuario diferente (por ejemplo, un backup del sistema que se ejecuta como root)."
}
],
"lastModified": "2026-06-17T01:52:56.513",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:gnu:tar:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "568B865E-7BA0-45A1-A944-575D49BC289E",
"versionEndIncluding": "1.30"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "C11E6FB0-C8C0-4527-9AA0-CB9B316F8F43"
},
{
"criteria": "cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "DEECE5FC-CACF-4496-A3E7-164736409252"
}
],
"operator": "OR"
}
]
},
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:opensuse:leap:15.0:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F1E78106-58E6-4D59-990F-75DA575BFAD9"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "cve@mitre.org"
}