CVE-2026-18206
Full vulnerability record from the local CVENow database.
Description
A flaw was found in the keycloak-services component of Keycloak, which provides identity and access management services. The issue occurs when a realm administrator uses a wildcard domain (like *.example.com) to restrict which hosts can register or update clients. Due to improper validation, the system accepts any hostname that ends with the specified domain suffix, even if it is not a legitimate subdomain. An attacker who can control the reverse DNS of their connection can bypass these host-based restrictions, potentially allowing unauthorized client modifications.
Severity
LOW
CVSS score
3.7
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-07-31 08:16:27.177000
Last modified
2026-11-07 12:17:46.227000
View original CVE JSON
{
"id": "CVE-2026-18206",
"sourceIdentifier": "[email protected]",
"published": "2026-07-31T08:16:27.177",
"lastModified": "2026-11-07T12:17:46.227",
"vulnStatus": "Modified",
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}
],
"affected": [
{
"source": "[email protected]",
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],
"metrics": {
"cvssMetricV31": [
{
"source": "[email protected]",
"type": "Secondary",
"cvssData": {
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"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N",
"baseScore": 3.7,
"baseSeverity": "LOW",
"attackVector": "NETWORK",
"attackComplexity": "HIGH",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
"integrityImpact": "LOW",
"availabilityImpact": "NONE"
},
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},
{
"source": "[email protected]",
"type": "Primary",
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],
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},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-20"
}
]
}
],
"configurations": [
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"references": [
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"url": "https://access.redhat.com/errata/RHSA-2026:95761",
"source": "[email protected]"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:95762",
"source": "[email protected]"
},
{
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"source": "[email protected]",
"tags": [
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},
{
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"source": "[email protected]",
"tags": [
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]
}