CVE-2026-3039: BIND 9 server memory exhaustion during GSS-API TKEY negotiation

High severity · published May 20, 2026

CVE-2026-3039

BIND 9 server memory exhaustion during GSS-API TKEY negotiation

7.5

CVSS

1.1%

EPSS

On KEV

Description

BIND servers that are configured to use TKEY-based authentication via GSS-API tokens are vulnerable to excessive memory consumption when receiving and processing maliciously-constructed packets. Typically these servers will be found in Active Directory integrated DNS deployments and/or Kerberos-secured DNS environments. This issue affects BIND 9 versions 9.0.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.9.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.

CVSS vector

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

Attack vector

Network

Complexity

Low

Privileges

None

User interaction

None

Confidentiality

None

Integrity

None

Availability

High

Scope

Unchanged

Exploitation

Is it being used?

Exploit prediction (EPSS)1.1% · higher than 65% of CVEs

Exploited in the wildNo evidence yet

CISA KEVNot listed

Ransomware campaign useNot known

Affected products

Which versions

BIND 9 · ISC

9.0.0 through 9.16.50; 9.18.0 through 9.18.48; 9.20.0 through 9.20.22; 9.21.0 through 9.21.21; 9.9.3-S1 through 9.16.50-S1; 9.18.11-S1 through 9.18.48-S1; +1 more · source: vendor

Bind · Isc

9.0.0 through 9.16.50; 9.18.0 before 9.18.49; 9.20.0 before 9.20.23; 9.21.0 before 9.21.22 · source: NVD

Red Hat Enterprise Linux 10 · Red Hat