CVE-2026-31681
Estado: ModificadaMedia (5.5)—
In the Linux kernel, the following vulnerability has been resolved:
netfilter: xt_multiport: validate range encoding in checkentry
ports_match_v1() treats any non-zero pflags entry as the start of a port range and unconditionally consumes the next ports[] element as the range end.
The checkentry path currently validates protocol, flags and count, but it does not validate the range encoding itself. As a result, malformed rules can mark the last slot as a range start or place two range starts back to back, leaving ports_match_v1() to step past the last valid ports[] element while interpreting the rule.
Leer descripción completaMostrar menos
Reject malformed multiport v1 rules in checkentry by validating that each range start has a following element and that the following element is not itself marked as another range start.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 5.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.17%
- Percentil entre todas las CVEs puntuadas: 6
- 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).
Tecnologías afectadas (1)
CWE
- NVD-CWE-noinfo
Referencias
- https://git.kernel.org/stable/c/1e4baa853f1cc4227e04f52d6860524707cfb294
- https://git.kernel.org/stable/c/36bf0d98e180a7c384c8d8a59b0d2d4b80e5eb16
- https://git.kernel.org/stable/c/8368ce8eb01f0b91111d814703696e780d0ef12f
- https://git.kernel.org/stable/c/8c5bf8f5b478f569191c4a7982de7cd5f5f73c1a
- https://git.kernel.org/stable/c/aec14808271f2bf2b656de6ff12dfe73c5fd3b67
- https://git.kernel.org/stable/c/b67d638cbee9975c765feb45c126e96ed11ec802
- https://git.kernel.org/stable/c/c9749f6232c845e31c21d4cc72200211df15d8a2
- https://git.kernel.org/stable/c/ff64c5bfef12461df8450e0f50bb693b5269c720
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-31681",
"cveTags": [],
"metrics": {
"cvssMetricV31": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 5.5,
"attackVector": "LOCAL",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 1.8
}
]
},
"affected": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"affectedData": [
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "8c5bf8f5b478f569191c4a7982de7cd5f5f73c1a",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "c9749f6232c845e31c21d4cc72200211df15d8a2",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "b67d638cbee9975c765feb45c126e96ed11ec802",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "36bf0d98e180a7c384c8d8a59b0d2d4b80e5eb16",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "aec14808271f2bf2b656de6ff12dfe73c5fd3b67",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "8368ce8eb01f0b91111d814703696e780d0ef12f",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "1e4baa853f1cc4227e04f52d6860524707cfb294",
"versionType": "git"
},
{
"status": "affected",
"version": "a89ecb6a2ef732d04058d87801e2b6bd7e5c7089",
"lessThan": "ff64c5bfef12461df8450e0f50bb693b5269c720",
"versionType": "git"
}
],
"programFiles": [
"net/netfilter/xt_multiport.c"
],
"defaultStatus": "unaffected"
},
{
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"product": "Linux",
"versions": [
{
"status": "affected",
"version": "2.6.17"
},
{
"status": "unaffected",
"version": "0",
"lessThan": "2.6.17",
"versionType": "semver"
},
{
"status": "unaffected",
"version": "5.10.258",
"versionType": "semver",
"lessThanOrEqual": "5.10.*"
},
{
"status": "unaffected",
"version": "5.15.209",
"versionType": "semver",
"lessThanOrEqual": "5.15.*"
},
{
"status": "unaffected",
"version": "6.1.175",
"versionType": "semver",
"lessThanOrEqual": "6.1.*"
},
{
"status": "unaffected",
"version": "6.6.136",
"versionType": "semver",
"lessThanOrEqual": "6.6.*"
},
{
"status": "unaffected",
"version": "6.12.83",
"versionType": "semver",
"lessThanOrEqual": "6.12.*"
},
{
"status": "unaffected",
"version": "6.18.24",
"versionType": "semver",
"lessThanOrEqual": "6.18.*"
},
{
"status": "unaffected",
"version": "6.19.14",
"versionType": "semver",
"lessThanOrEqual": "6.19.*"
},
{
"status": "unaffected",
"version": "7.0",
"versionType": "original_commit_for_fix",
"lessThanOrEqual": "*"
}
],
"programFiles": [
"net/netfilter/xt_multiport.c"
],
"defaultStatus": "affected"
}
]
},
{
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e",
"affectedData": [
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"versions": [
{
"status": "affected",
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518-4 PN/DP MFP",
"versions": [
{
"status": "affected",
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"versions": [
{
"status": "affected",
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
},
{
"vendor": "Siemens",
"product": "SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP",
"versions": [
{
"status": "affected",
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
},
{
"vendor": "Siemens",
"product": "SIPLUS S7-1500 CPU 1518-4 PN/DP MFP",
"versions": [
{
"status": "affected",
"version": "V3.1.6",
"lessThan": "*",
"versionType": "custom"
}
],
"defaultStatus": "unknown"
}
]
}
],
"published": "2026-04-25T09:16:01.800",
"references": [
{
"url": "https://git.kernel.org/stable/c/1e4baa853f1cc4227e04f52d6860524707cfb294",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/36bf0d98e180a7c384c8d8a59b0d2d4b80e5eb16",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8368ce8eb01f0b91111d814703696e780d0ef12f",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/8c5bf8f5b478f569191c4a7982de7cd5f5f73c1a",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/aec14808271f2bf2b656de6ff12dfe73c5fd3b67",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/b67d638cbee9975c765feb45c126e96ed11ec802",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/c9749f6232c845e31c21d4cc72200211df15d8a2",
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://git.kernel.org/stable/c/ff64c5bfef12461df8450e0f50bb693b5269c720",
"tags": [
"Patch"
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
},
{
"url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html",
"source": "0b142b55-0307-4c5a-b3c9-f314f3fb7c5e"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Primary",
"source": "nvd@nist.gov",
"description": [
{
"lang": "en",
"value": "NVD-CWE-noinfo"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: xt_multiport: validate range encoding in checkentry\n\nports_match_v1() treats any non-zero pflags entry as the start of a\nport range and unconditionally consumes the next ports[] element as\nthe range end.\n\nThe checkentry path currently validates protocol, flags and count, but\nit does not validate the range encoding itself. As a result, malformed\nrules can mark the last slot as a range start or place two range starts\nback to back, leaving ports_match_v1() to step past the last valid\nports[] element while interpreting the rule.\n\nReject malformed multiport v1 rules in checkentry by validating that\neach range start has a following element and that the following element\nis not itself marked as another range start."
}
],
"lastModified": "2026-09-08T09:17:59.380",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "A7B9FFD8-E991-452F-9730-FADDA1A54E82",
"versionEndExcluding": "6.6.136",
"versionStartIncluding": "2.6.17"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "7F0AE5B5-23AC-4DCC-B37A-51CA1DAE7BA8",
"versionEndExcluding": "6.12.83",
"versionStartIncluding": "6.7"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "8126B8B8-6D0B-4443-86C1-672AEE893555",
"versionEndExcluding": "6.18.24",
"versionStartIncluding": "6.13"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "D6A8A074-BBF4-4803-ABED-519A839435BB",
"versionEndExcluding": "6.19.14",
"versionStartIncluding": "6.19"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6"
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}