CVE-2023-6918
Full vulnerability record from the local CVENow database.
Description
A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection.
Severity
MEDIUM
CVSS score
5.3
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2023-12-19 00:15:08.460000
Last modified
2026-11-06 14:17:02.333000
View original CVE JSON
{
"id": "CVE-2023-6918",
"sourceIdentifier": "[email protected]",
"published": "2023-12-19T00:15:08.460",
"lastModified": "2026-11-06T14:17:02.333",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection."
},
{
"lang": "es",
"value": "Se encontró un fallo en la capa abstracta de implementación de libssh para operaciones de resumen de mensajes (MD) implementadas por diferentes backends criptográficos compatibles. Los valores de retorno de estos no se verificaron correctamente, lo que podría causar fallas en situaciones de poca memoria, desreferencias NULL, fallas o uso de la memoria no inicializada como entrada para el KDF. En este caso, las claves que no coinciden resultarán en fallas de descifrado/integridad, lo que terminará la conexión."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream",
"cpe:/o:redhat:enterprise_linux:8::baseos"
],
"versions": [
{
"version": "0:0.9.6-14.el8",
"lessThan": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8::appstream",
"cpe:/o:redhat:enterprise_linux:8::baseos"
],
"versions": [
{
"version": "0:0.9.6-14.el8",
"lessThan": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream",
"cpe:/o:redhat:enterprise_linux:9::baseos"
],
"versions": [
{
"version": "0:0.10.4-13.el9",
"lessThan": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9::appstream",
"cpe:/o:redhat:enterprise_linux:9::baseos"
],
"versions": [
{
"version": "0:0.10.4-13.el9",
"lessThan": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 6",
"defaultStatus": "unknown",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh2",
"cpes": [
"cpe:/o:redhat:rhel_els:6"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"defaultStatus": "unknown",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"defaultStatus": "unknown",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh2",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L",
"baseScore": 3.7,
"baseSeverity": "LOW",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 2.2,
"impactScore": 1.4
},
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"baseScore": 5.3,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "LOW"
},
"exploitabilityScore": 3.9,
"impactScore": 1.4
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-252"
}
]
},
{
"source": "[email protected]",
"type": "Primary",
"description": [
{
"lang": "en",
"value": "CWE-252"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*",
"versionStartIncluding": "0.9.0",
"versionEndExcluding": "0.9.8",
"matchCriteriaId": "4836788D-9936-404F-B0A8-DDDAC3969F20"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*",
"versionStartIncluding": "0.10.0",
"versionEndExcluding": "0.10.6",
"matchCriteriaId": "BCB546AC-788C-422E-B6BD-756BF39BD0F5"
}
]
}
]
},
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*",
"matchCriteriaId": "CC559B26-5DFC-4B7A-A27C-B77DE755DFF9"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*",
"matchCriteriaId": "B8EDB836-4E6A-4B71-B9B2-AA3E03E0F646"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:redhat:enterprise_linux:8.0:*:*:*:*:*:*:*",
"matchCriteriaId": "F4CFF558-3C47-480D-A2F0-BABF26042943"
},
{
"vulnerable": true,
"criteria": "cpe:2.3:o:redhat:enterprise_linux:9.0:*:*:*:*:*:*:*",
"matchCriteriaId": "7F6FB57C-2BC7-487C-96DD-132683AEB35D"
}
]
}
]
}
],
"references": [
{
"url": "https://access.redhat.com/errata/RHSA-2024:2504",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/errata/RHSA-2024:3233",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2023-6918",
"source": "[email protected]",
"tags": [
"Mailing List",
"Vendor Advisory"
]
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2254997",
"source": "[email protected]",
"tags": [
"Issue Tracking",
"Third Party Advisory"
]
},
{
"url": "https://www.libssh.org/2023/12/18/libssh-0-10-6-and-libssh-0-9-8-security-releases/",
"source": "[email protected]",
"tags": [
"Release Notes"
]
},
{
"url": "https://www.libssh.org/security/advisories/CVE-2023-6918.txt",
"source": "[email protected]",
"tags": [
"Vendor Advisory"
]
},
{
"url": "https://access.redhat.com/errata/RHSA-2024:2504",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://access.redhat.com/errata/RHSA-2024:3233",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2023-6918",
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Mailing List",
"Vendor Advisory"
]
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2254997",
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Issue Tracking",
"Third Party Advisory"
]
},
{
"url": "https://lists.fedoraproject.org/archives/list/[email protected]/message/LZQVUHWVWRH73YBXUQJOD6CKHDQBU3DM/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://lists.fedoraproject.org/archives/list/[email protected]/message/MKQRBF3DWMWPH36LBCOBUTSIZRTPEZXB/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://security.netapp.com/advisory/ntap-20250214-0009/",
"source": "af854a3a-2127-422b-91ae-364da2661108"
},
{
"url": "https://www.libssh.org/2023/12/18/libssh-0-10-6-and-libssh-0-9-8-security-releases/",
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Release Notes"
]
},
{
"url": "https://www.libssh.org/security/advisories/CVE-2023-6918.txt",
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Vendor Advisory"
]
}
]
}