CVE-2026-58218

A flaw was found in Samba's internal DNS server where unauthenticated TKEY registration requests were added to the TKEY name cache before being rejected. A remote, unauthenticated attacker can exploit this behavior by sending a large number of TKEY requests with arbitrary names, exhausting the cache and evicting legitimate TKEY entries. This can prevent legitimate TSIG authentication for signed DNS queries, resulting in a denial of service.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-58218
https://bugzilla.redhat.com/show_bug.cgi?id=2502728
https://bugzilla.samba.org/show_bug.cgi?id=16115
https://www.samba.org/samba/security/CVE-2026-58218.html

Configurations

No configuration.

History

30 Jul 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-30 14:17

Updated : 2026-07-30 19:18

NVD link : CVE-2026-58218

Mitre link : CVE-2026-58218

CVE.ORG link : CVE-2026-58218

JSON object : View

Products Affected

No product.

CWE

CWE-410

Insufficient Resource Pool

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