Vulnerability Report

CVE-2026-3593

Title: Use-after-free in BIND DNS-over-HTTPS

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-3593.

CWE Category CWE-416
Published Date May 20, 2026
Modified Date May 21, 2026
Exploit Status Not Found
Score 7.4 CVSS v3.1
Exploit Probability (EPSS)
0.04%

Vulnerability Summary

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.

Impacted Vendors

I
isc 1

Reference Links

https://downloads.isc.org/isc/bind9/9.20.23 https://downloads.isc.org/isc/bind9/9.21.22 https://kb.isc.org/docs/cve-2026-3593
CVSS v3.1
Source Entity [email protected]
Severity HIGH
7.4
Attack Vector
NETWORK
Complexity
HIGH
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H
CVSS v3.1
Source Entity [email protected]
Severity CRITICAL
9.8
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-3593 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity HIGH
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:H

Affected Stack

No specific products linked.