CVE-2026-3593

high

Description

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.

References

https://kb.isc.org/docs/cve-2026-3593

https://downloads.isc.org/isc/bind9/9.21.22

https://downloads.isc.org/isc/bind9/9.20.23

Details

Source: Mitre, NVD

Published: 2026-05-20

Updated: 2026-05-20

Risk Information

CVSS v2

Base Score: 7.1

Vector: CVSS2#AV:N/AC:H/Au:N/C:C/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.4

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

Severity: High