CVE-2026-3593

critical
Published 2026-05-20 · Modified 2026-05-21
CVSS v3
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS v2
VIR risk
9.8

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.

Predictions

Exploit likelihood
97%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2026-3593.html

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2026-3593

vendor Authored 2026-05-27

Vendor advisory: security-officer@isc.org — https://kb.isc.org/docs/cve-2026-3593

vendor Authored 2026-05-27

Vendor advisory: security-officer@isc.org — https://downloads.isc.org/isc/bind9/9.21.22

vendor Authored 2026-05-27

Vendor advisory: security-officer@isc.org — https://downloads.isc.org/isc/bind9/9.20.23

OS impact

OSVersionStatusFixed in
debian debianbookwormfixed0
debian debianbullseyefixed0
debian debianforkyfixed1:9.20.23-1
debian debiansidfixed1:9.20.23-1
debian debiantrixiefixed1:9.20.23-1~deb13u1
suse slesaffected

Application impact

VendorProductVersionsFixed
iscbind{"startIncluding":"9.20.0","endExcluding":"9.20.23"}9.20.23

References

CWEs

CWE-416

Verify integrity in audit chain (admin only). AS-IS.