CVE-2026-13204: If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist an RR

This month

HIGH 7.5REMOTE

CVE-2026-13204 is a high-severity flaw (CVSS 7.5) affecting affected software. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist an RRSIG for only one of these types, then BIND may exit unexpectedly with an assertion while validating this proof. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

Why this priority

High severity
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	0.5% (top 56%)
CISA exploited list	No
Weakness	CWE-617
Published	2026-07-22
Last modified	2026-10-24

Publisher (CNA): Internet Systems Consortium (ISC)

Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Timeline

2026-07-22 15:16 UTCPublished CVE record published
2026-10-24 18:10 UTCUpdated Record last modified

Exact fixes by distribution

Fedora 46 · uv · FIXED · 0.13.5-2.fc46 · FEDORA-2026-0a45cde16b · source

sudo dnf upgrade --advisory=FEDORA-2026-0a45cde16b

Fedora ELN · oo7 · FIXED · 0.7.0~beta-3.eln159 · FEDORA-2026-f348262964 · source

sudo dnf upgrade --advisory=FEDORA-2026-f348262964

Ubuntu 22.04 · bind9 · FIXED · 1:9.18.39-0ubuntu0.22.04.6

sudo apt update && sudo apt install --only-upgrade bind9 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' bind9)" ge "1:9.18.39-0ubuntu0.22.04.6" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 24.04 · bind9 · FIXED · 1:9.18.39-0ubuntu0.24.04.7

sudo apt update && sudo apt install --only-upgrade bind9 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' bind9)" ge "1:9.18.39-0ubuntu0.24.04.7" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 20.04 · bind9 · FIXED · 1:9.18.30-0ubuntu0.20.04.2+esm3

sudo apt update && sudo apt install --only-upgrade bind9 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' bind9)" ge "1:9.18.30-0ubuntu0.20.04.2+esm3" && echo PATCHED || echo STILL-VULNERABLE

Ubuntu 20.04 · isc-dhcp · NOT AFFECTED

Ubuntu 22.04 · isc-dhcp · NOT AFFECTED

Debian 12 · bind9 · FIXED · 1:9.18.49-1~deb12u2

sudo apt update && sudo apt install --only-upgrade bind9 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' bind9)" ge "1:9.18.49-1~deb12u2" && echo PATCHED || echo STILL-VULNERABLE

Debian 13 · bind9 · FIXED · 1:9.20.26-1~deb13u1

sudo apt update && sudo apt install --only-upgrade bind9 dpkg --compare-versions "$(dpkg-query -W -f='${Version}' bind9)" ge "1:9.20.26-1~deb13u1" && echo PATCHED || echo STILL-VULNERABLE

RHEL 10 · bind · FIXED · bind-9.18.33-15.el10_2.10

sudo dnf upgrade --advisory=RHSA-2026:55437 rpm -q bind

RHEL 7 Extended Lifecycle Support · bind · FIXED · bind-9.11.4-26.P2.el7_9.21

sudo dnf upgrade --advisory=RHSA-2026:60383 rpm -q bind

RHEL 8 · bind9.16 · FIXED · bind9.16-9.16.23-0.22.el8_10.12

sudo dnf upgrade --advisory=RHSA-2026:54509 rpm -q bind9.16

RHEL 8 · bind · FIXED · bind-9.11.36-16.el8_10.14

sudo dnf upgrade --advisory=RHSA-2026:54654 rpm -q bind

RHEL 8.6 Advanced Mission Critical Update Support · bind9.16 · FIXED · bind9.16-9.16.23-0.7.el8_6.11

sudo dnf upgrade --advisory=RHSA-2026:80501 rpm -q bind9.16

Alpine 3.22 · bind · FIXED · bind-9.20.26-r0

apk add --upgrade bind apk info -v bind

Alpine 3.23 · bind · FIXED · bind-9.20.26-r0

apk add --upgrade bind apk info -v bind

Alpine 3.24 · bind · FIXED · bind-9.20.26-r0

apk add --upgrade bind apk info -v bind

Amazon Linux 2023 · see advisory · FIXED · ALAS2023-2026-2040 · source

sudo dnf update --advisory=ALAS2023-2026-2040

Amazon Linux 2 · see advisory · FIXED · ALAS2-2026-3854 · source

sudo yum update --advisory=ALAS2-2026-3854

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2026-13204?

No fixed release is listed yet. Watch the vendor advisory and apply any mitigation shown on this page.

Is CVE-2026-13204 being exploited?

CVE-2026-13204 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2026-13204 affect?

CVE-2026-13204 affects affected software. Severity is high (CVSS 7.5). If a provably insecure domain is covered by both an NSEC and NSEC3 record at the parent, and there exist an RRSIG for only one of these types, then BIND may exit unexpectedly with an assertion while validating this proof. This issue affects

How urgent is CVE-2026-13204?

Priority 42/100. High severity; Remotely exploitable, no login, no user action

Software pages

BIND DNS vulnerabilities

References

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