CVE-2026-18663
Full vulnerability record from the local CVENow database.
Description
A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service.
Severity
MEDIUM
CVSS score
5.9
(v3.1)
Vulnerability status
Awaiting Analysis
Source identifier
Published
2026-08-12 10:17:18.437000
Last modified
2026-11-05 20:17:53.410000
View original CVE JSON
{
"id": "CVE-2026-18663",
"sourceIdentifier": "[email protected]",
"published": "2026-08-12T10:17:18.437",
"lastModified": "2026-11-05T20:17:53.410",
"vulnStatus": "Awaiting Analysis",
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "A flaw was found in 389-ds-base. The get_ldapmessage_controls_ext() function frees the parsed controls array on the Session Tracking critical-control rejection path without clearing the SLAPI_REQCONTROLS pblock slot. Operation teardown then frees the same pointer again, causing a double-free. An unauthenticated remote attacker can trigger this with a single BIND request carrying a critical Session Tracking control, resulting in heap corruption and potential denial of service."
}
],
"affected": [
{
"source": "[email protected]",
"affectedData": [
{
"vendor": "Red Hat",
"product": "Red Hat Directory Server 11",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "redhat-ds:11/389-ds-base",
"cpes": [
"cpe:/a:redhat:directory_server:11"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Directory Server 12",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "redhat-ds:12/389-ds-base",
"cpes": [
"cpe:/a:redhat:directory_server:12"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Directory Server 13",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds-base",
"cpes": [
"cpe:/a:redhat:directory_server:13"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"defaultStatus": "affected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds-base",
"cpes": [
"cpe:/a:redhat:enterprise_linux:10"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 6",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds-base",
"cpes": [
"cpe:/o:redhat:rhel_els:6"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds-base",
"cpes": [
"cpe:/o:redhat:rhel_els:7"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds:1.4/389-ds-base",
"cpes": [
"cpe:/a:redhat:enterprise_linux:8"
]
},
{
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"defaultStatus": "unaffected",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"packageName": "389-ds-base",
"cpes": [
"cpe:/a:redhat:enterprise_linux:9"
]
}
]
}
],
"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
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"timestamp": "2026-08-13T15:40:56.481579Z",
"id": "CVE-2026-18663",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"version": "2.0.3"
}
}
]
},
"weaknesses": [
{
"source": "[email protected]",
"type": "Secondary",
"description": [
{
"lang": "en",
"value": "CWE-415"
}
]
}
],
"references": [
{
"url": "https://access.redhat.com/security/cve/CVE-2026-18663",
"source": "[email protected]"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2510631",
"source": "[email protected]"
}
]
}