CVE-2026-3593

A use-after-free vulnerability exists within the DNS-over-HTTPS implementation. This issue affects BIND 9 versions 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, and 9.20.9-S1 through 9.20.22-S1. BIND 9 versions 9.18.0 through 9.18.48 and 9.18.11-S1 through 9.18.48-S1 are NOT affected.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://downloads.isc.org/isc/bind9/9.20.23	Patch
https://downloads.isc.org/isc/bind9/9.21.22	Patch
https://kb.isc.org/docs/cve-2026-3593	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:isc:bind:::::-:::*
	cpe:2.3:a:isc:bind:::::-:::*

History

21 May 2026, 15:24

Type	Values Removed	Values Added
References	~~() https://downloads.isc.org/isc/bind9/9.20.23 -~~	() https://downloads.isc.org/isc/bind9/9.20.23 - Patch
References	~~() https://downloads.isc.org/isc/bind9/9.21.22 -~~	() https://downloads.isc.org/isc/bind9/9.21.22 - Patch
References	~~() https://kb.isc.org/docs/cve-2026-3593 -~~	() https://kb.isc.org/docs/cve-2026-3593 - Vendor Advisory
CPE		cpe:2.3:a:isc:bind:::::-:::*
First Time		Isc bind Isc

20 May 2026, 13:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-20 13:16

Updated : 2026-05-21 15:24

NVD link : CVE-2026-3593

Mitre link : CVE-2026-3593

CVE.ORG link : CVE-2026-3593

JSON object : View

Products Affected

isc

bind

CWE

CWE-416

Use After Free

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