CVE-2026-58218 (GCVE-0-2026-58218)

Vulnerability from cvelistv5 – Published: 2026-07-30 14:01 – Updated: 2026-07-30 17:37
VLAI
Title
Samba: dns signing dos via tkey name cache exhaustion
Summary
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
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-410 - Insufficient Resource Pool
Assigner
References
Impacted products
Date Public
2026-07-28 10:00
Credits
Red Hat would like to thank Andrew Tridgell (Samba Team) and Tristan Madani (Talence Security) for reporting this issue.
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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