CVE-2026-58216

An out-of-bounds read flaw was found in Samba's Kerberos Key Distribution Center's (KDC) password change (kpasswd) service. When processing malformed ASN.1-encoded Kerberos password change request, Samba server miscalculates the structure size and attempts to read up to six bytes beyond the end of the allocated buffer. While this out-of-bounds read typically results in a harmless decryption failure, if the read hits unmapped memory, it causes the KDC process to crash. An authenticated attacker can send a specially crafted kpasswd request containing malformed ASN.1 data to trigger the out-of-bounds read, which may cause the KDC process to terminate, resulting in a denial of service.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.6 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-58216
https://bugzilla.redhat.com/show_bug.cgi?id=2502721
https://bugzilla.samba.org/show_bug.cgi?id=16087
https://www.samba.org/samba/security/CVE-2026-58216.html

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-30 16:17

Updated : 2026-07-31 23:17

NVD link : CVE-2026-58216

Mitre link : CVE-2026-58216

CVE.ORG link : CVE-2026-58216

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

{"id": "CVE-2026-58216", "cveTags": [], "metrics": {"ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2026-58216", "role": "CISA Coordinator", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "version": "2.0.3", "timestamp": "2026-07-31T22:57:32.483621Z"}}], "cvssMetricV31": [{"type": "Secondary", "source": "secalert@redhat.com", "cvssData": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.3, "attackVector": "NETWORK", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "HIGH", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}, "impactScore": 3.6, "exploitabilityScore": 1.6}]}, "affected": [{"source": "secalert@redhat.com", "affectedData": [{"cpes": ["cpe:/o:redhat:enterprise_linux:10"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 10", "packageName": "samba", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 6", "packageName": "samba", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:6"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 6", "packageName": "samba4", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:7"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 7", "packageName": "samba", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:8"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 8", "packageName": "samba", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/o:redhat:enterprise_linux:9"], "vendor": "Red Hat", "product": "Red Hat Enterprise Linux 9", "packageName": "samba", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}, {"cpes": ["cpe:/a:redhat:openshift:4"], "vendor": "Red Hat", "product": "Red Hat OpenShift Container Platform 4", "packageName": "rhcos", "collectionURL": "https://access.redhat.com/downloads/content/package-browser/", "defaultStatus": "unknown"}]}], "published": "2026-07-30T16:17:14.767", "references": [{"url": "https://access.redhat.com/security/cve/CVE-2026-58216", "source": "secalert@redhat.com"}, {"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2502721", "source": "secalert@redhat.com"}, {"url": "https://bugzilla.samba.org/show_bug.cgi?id=16087", "source": "secalert@redhat.com"}, {"url": "https://www.samba.org/samba/security/CVE-2026-58216.html", "source": "secalert@redhat.com"}], "vulnStatus": "Awaiting Analysis", "weaknesses": [{"type": "Secondary", "source": "secalert@redhat.com", "description": [{"lang": "en", "value": "CWE-125"}]}], "descriptions": [{"lang": "en", "value": "An out-of-bounds read flaw was found in Samba's Kerberos Key Distribution Center's (KDC) password change (kpasswd) service. When processing malformed ASN.1-encoded Kerberos password change request, Samba server miscalculates the structure size and attempts to read up to six bytes beyond the end of the allocated buffer. While this out-of-bounds read typically results in a harmless decryption failure, if the read hits unmapped memory, it causes the KDC process to crash. An authenticated attacker can send a specially crafted kpasswd request containing malformed ASN.1 data to trigger the out-of-bounds read, which may cause the KDC process to terminate, resulting in a denial of service."}], "lastModified": "2026-07-31T23:17:25.703", "sourceIdentifier": "secalert@redhat.com"}