CVE-2026-3593

HIGH

Heap use-after-free vulnerability in BIND 9 DNS-over-HTTPS implementation

Title source: cna
STIX 2.1

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 (3)

Core 3
Core References
Vendor Advisory vendor-advisory
CVE-2026-3593
https://kb.isc.org/docs/cve-2026-3593

Scores

CVSS v3 7.4
EPSS 0.0002
EPSS Percentile 5.2%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation none
Automatable no
Technical Impact partial

Details

CWE
CWE-416
Status published
Products (6)
isc/bind 9.20.0 - 9.20.23
ISC/BIND 9 9.18.0 - 9.18.48
ISC/BIND 9 9.18.11-S1 - 9.18.48-S1
ISC/BIND 9 9.20.0 - 9.20.22
ISC/BIND 9 9.20.9-S1 - 9.20.22-S1
ISC/BIND 9 9.21.0 - 9.21.21
Published May 20, 2026
Tracked Since May 20, 2026