Description
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.
Severity (CVSS)
| Base score | 5.3 |
|---|---|
| Severity | Medium |
| Version | CVSS 3.1 |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L |
| Provided by | CNA |
Weaknesses
- CWE-410 — Insufficient Resource Pool
Affected products
| Vendor | Product | Versions |
|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 | — |
| Red Hat | Red Hat Enterprise Linux 6 | — |
| Red Hat | Red Hat Enterprise Linux 6 | — |
| Red Hat | Red Hat Enterprise Linux 7 | — |
| Red Hat | Red Hat Enterprise Linux 8 | — |
| Red Hat | Red Hat Enterprise Linux 9 | — |
| Red Hat | Red Hat OpenShift Container Platform 4 | — |
References
- https://access.redhat.com/security/cve/CVE-2026-58218 (vdb-entry x_refsource_REDHAT)
- https://bugzilla.redhat.com/show_bug.cgi?id=2502728 (issue-tracking x_refsource_REDHAT)
- https://bugzilla.samba.org/show_bug.cgi?id=16115
- https://www.samba.org/samba/security/CVE-2026-58218.html
Generated from the official CVE List on 31 Jul 2026 07:05 UTC.