CVE-2026-5950
MEDIUM EPSS 41.9%
Published May 20, 20261mo ago · Modified Jun 17, 20262w ago
5.3 CVSS 3.1
Published May 20, 2026 1mo ago
Last Modified Jun 17, 2026 2w ago
Description
An unbounded resend loop vulnerability exists in the BIND 9 resolver state machine during bad-server handling, enabling a remote unauthenticated attacker to cause severe resource exhaustion by sending queries that trigger specific retry conditions. This issue affects BIND 9 versions 9.18.36 through 9.18.48, 9.20.8 through 9.20.22, 9.21.7 through 9.21.21, 9.18.36-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability Low
Threat Intelligence
EPSS Exploit Probability
41.9% percentile
Exploit & Patch Status
No Known Exploit
Patch Available
Weaknesses 1
CWE-606
Affected Products 3
References 4
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.18.49
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.20.23
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.21.22
- kb.isc.org https://kb.isc.org/docs/cve-2026-5950
Remediation
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.18.49
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.20.23
- downloads.isc.org https://downloads.isc.org/isc/bind9/9.21.22