CVE-2026-0967
Full vulnerability record from the local CVENow database.
Description
A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client.
Severity
MEDIUM
CVSS score
5.5
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-03-26 21:17:00.970000
Last modified
2026-11-06 18:17:30.910000
View original CVE JSON
{
"id": "CVE-2026-0967",
"sourceIdentifier": "[email protected]",
"published": "2026-03-26T21:17:00.970",
"lastModified": "2026-11-06T18:17:30.910",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client."
},
{
"lang": "es",
"value": "Se encontró una vulnerabilidad en libssh. Un atacante remoto, al controlar los archivos de configuración del cliente o los archivos known_hosts, podría crear nombres de host específicos que, al ser procesados por la función `match_pattern()`, pueden llevar a un retroceso ineficiente de expresiones regulares. Esto puede causar tiempos de espera y agotamiento de recursos, lo que resulta en una denegación de servicio (DoS) para el cliente."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh",
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"versions": [
{
"version": "0:0.12.0-2.el10",
"lessThan": "*",
"versionType": "rpm",
"status": "unaffected"
}
]
},
{
"vendor": "Red Hat",
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"packageName": "libssh",
"cpes": [
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],
"versions": [
{
"version": "0:0.10.4-18.el9",
"lessThan": "*",
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}
]
},
{
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},
{
"vendor": "Red Hat",
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"packageName": "libssh2",
"cpes": [
"cpe:/o:redhat:rhel_els:6"
]
},
{
"vendor": "Red Hat",
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"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh2",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
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},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
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"packageName": "libssh",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Hardened Images",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "libssh2",
"cpes": [
"cpe:/a:redhat:hummingbird:1"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat OpenShift Container Platform 4",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "openshift/ose-rhel-coreos-8",
"cpes": [
"cpe:/a:redhat:openshift:4"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat OpenShift Container Platform 4",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "openshift/ose-rhel-coreos-9",
"cpes": [
"cpe:/a:redhat:openshift:4"
]
}
]
}
],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
"version": "3.1",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H",
"baseScore": 5.5,
"baseSeverity": "MEDIUM",
"attackVector": "LOCAL",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 1.8,
"impactScore": 3.6
}
],
"cvssMetricV30": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
"version": "3.0",
"vectorString": "CVSS:3.0/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L",
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"attackComplexity": "HIGH",
"privilegesRequired": "LOW",
"userInteraction": "REQUIRED",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "LOW"
},
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],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-03-27T13:36:27.743421Z",
"id": "CVE-2026-0967",
"options": [
{
"exploitation": "none"
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{
"automatable": "no"
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{
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],
"role": "CISA Coordinator",
"version": "2.0.3"
}
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]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-1333"
}
]
}
],
"configurations": [
{
"nodes": [
{
"operator": "OR",
"negate": false,
"cpeMatch": [
{
"vulnerable": true,
"criteria": "cpe:2.3:a:libssh:libssh:*:*:*:*:*:*:*:*",
"versionEndIncluding": "0.11.3",
"matchCriteriaId": "2366D711-FD0B-4A04-92BA-DE6DA0ED1BCF"
},
{
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{
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"matchCriteriaId": "D65C2163-CFC2-4ABB-8F4E-CB09CEBD006C"
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]
}
],
"references": [
{
"url": "https://access.redhat.com/errata/RHSA-2026:18160",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:18683",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2026-0967",
"source": "[email protected]",
"tags": [
"Third Party Advisory"
]
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2436981",
"source": "[email protected]",
"tags": [
"Third Party Advisory"
]
},
{
"url": "https://www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-releases/",
"source": "[email protected]",
"tags": [
"Release Notes"
]
}
]
}