CVE-2026-40355
Full vulnerability record from the local CVENow database.
Description
In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, causing the process to terminate in parse_nego_message.
Severity
HIGH
CVSS score
7.5
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-04-28 06:16:03.663000
Last modified
2026-10-26 21:10:00.170000
View original CVE JSON
{
"id": "CVE-2026-40355",
"sourceIdentifier": "[email protected]",
"published": "2026-04-28T06:16:03.663",
"lastModified": "2026-10-26T21:10:00.170",
"vulnStatus": "Modified",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, causing the process to terminate in parse_nego_message."
},
{
"lang": "es",
"value": "En MIT Kerberos 5 (también conocido como krb5) anterior a la versión 1.22.3, existe una desreferencia de puntero NULL si una aplicación llama a gss_accept_sec_context() en un sistema con un mecanismo NegoEx registrado en /etc/gss/mech. Un atacante remoto no autenticado puede activar esto, lo que provoca la terminación del proceso en parse_nego_message."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "MIT",
"product": "Kerberos 5",
"defaultStatus": "unaffected",
"versions": [
{
"version": "1.18",
"lessThan": "1.22.3",
"versionType": "custom",
"status": "affected"
}
]
}
]
},
{
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{
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],
"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:H",
"baseScore": 5.9,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"availabilityImpact": "HIGH"
},
"exploitabilityScore": 2.2,
"impactScore": 3.6
},
{
"source": "[email protected]",
"type": "Primary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
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"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
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"availabilityImpact": "HIGH"
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],
"ssvcV203": [
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"ssvcData": {
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"id": "CVE-2026-40355",
"options": [
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},
{
"automatable": "no"
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{
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}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-476"
}
]
}
],
"configurations": [
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"nodes": [
{
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"cpeMatch": [
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"matchCriteriaId": "7A5665F4-71F4-4A71-A0A0-1E1F2BECA288"
}
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}
],
"references": [
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"source": "[email protected]",
"tags": [
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]
},
{
"url": "https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f",
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"tags": [
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},
{
"url": "https://web.mit.edu/kerberos/advisories/",
"source": "[email protected]",
"tags": [
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]
},
{
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}