CVE-2026-3593: Heap use-after-free vulnerability in BIND 9 DNS-over-HTTPS implementation

Overview

Severity

High (CVSS 7.4)

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H

Exploit Status

Not Exploited

Patch Tuesday

2026-May

Released

2026-05-23

EPSS Score

0.02% (percentile: 5.3%)

Affected Products (1)

Other

• 21351-17084

Revision History

• 2026-05-23: Information published.