CVE-2018-5740 — A flaw in the "deny-answer-aliases" feature can cause an assertion failure in named

Description

"deny-answer-aliases" is a little-used feature intended to help recursive server operators protect end users against DNS rebinding attacks, a potential method of circumventing the security model used by client browsers. However, a defect in this feature makes it easy, when the feature is in use, to experience an assertion failure in name.c. Affects BIND 9.7.0->9.8.8, 9.9.0->9.9.13, 9.10.0->9.10.8, 9.11.0->9.11.4, 9.12.0->9.12.2, 9.13.0->9.13.2.

Affected products

Vendor	Product	Affected	Fixed
ISC	BIND 9	BIND 9 9.7.0->9.8.8, 9.9.0->9.9.13, 9.10.0->9.10.8, 9.11.0->9.11.4, 9.12.0->9.12.2, 9.13.0->9.13.2	—

Fixed in Linux distributions

Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.

Debian

Security tracker ↗

Release	Package	Fixed in	Advisory
Debian 14	bind9	1:9.11.4.P1+dfsg-1	—
Debian 13	bind9	1:9.11.4.P1+dfsg-1	—
Debian 12	bind9	1:9.11.4.P1+dfsg-1	—
Debian 9	bind9	1:9.10.3.dfsg.P4-12.3+deb9u10	DLA-2807-1
Debian 8	bind9	1:9.9.5.dfsg-9+deb8u16	DLA-1485-1

Ubuntu

Security tracker ↗

Release	Package	Fixed in	Advisory
Ubuntu 18.04 LTS	bind9	1:9.11.3+dfsg-1ubuntu1.2	USN-3769-1
Ubuntu 16.04 LTS	bind9	1:9.10.3.dfsg.P4-8ubuntu1.11	USN-3769-1
Ubuntu 14.04 LTS	bind9	1:9.9.5.dfsg-3ubuntu0.18	USN-3769-1

Red Hat

Security tracker ↗

Release	Package	Fixed in	Advisory
RHEL 7	bind +13	32:9.9.4-61.el7_5.1	RHSA-2018:2570
RHEL 6	bind +5	32:9.8.2-0.68.rc1.el6_10.1	RHSA-2018:2571

SUSE

Security tracker ↗

Release	Package	Fixed in	Advisory
SLES 15 SP1	bind	9.11.2-12.11.2	SUSE-SU-2019:1407-1
SLES 15	bind	9.11.2-12.11.2	SUSE-SU-2019:1407-1
SLES 12 SP4	bind	9.11.2-3.10.1	SUSE-SU-2019:2502-1
SLES 12	bind	9.9.9P1-28.42.1	SUSE-SU-2019:1449-1
SLES 11 SP4	bind	9.9.6P1-0.51.15.4	SUSE-SU-2019:14074-1

Show 2 more (older releases, extended support, other products)

Release	Package	Fixed in	Advisory
SLES for SAP 12 SP4	bind	9.11.2-3.10.1	SUSE-SU-2019:2502-1
SUSE Linux Enterprise Point of Sale 11 SP3	bind	9.9.6P1-0.51.15.4	SUSE-SU-2019:14074-1

openSUSE

Security tracker ↗

Release	Package	Fixed in	Advisory
openSUSE Leap 15.1	bind	9.11.2-lp151.11.3.1	openSUSE-SU-2019:1533-1
openSUSE Leap 15.0	bind	9.11.2-lp151.11.3.1	openSUSE-SU-2019:1533-1

Alpine

Security tracker ↗

Release	Package	Fixed in	Advisory
Alpine v3.24	bind	9.12.2_p1-r0	—
Alpine v3.23	bind	9.12.2_p1-r0	—
Alpine v3.22	bind	9.12.2_p1-r0	—
Alpine v3.21	bind	9.12.2_p1-r0	—
Alpine v3.20	bind	9.12.2_p1-r0	—

Show 15 more (older releases, extended support, other products)

Release	Package	Fixed in	Advisory
Alpine v3.19	bind	9.12.2_p1-r0	—
Alpine v3.18	bind	9.12.2_p1-r0	—
Alpine v3.17	bind	9.12.2_p1-r0	—
Alpine v3.16	bind	9.12.2_p1-r0	—
Alpine v3.15	bind	9.12.2_p1-r0	—
Alpine v3.14	bind	9.12.2_p1-r0	—
Alpine v3.13	bind	9.12.2_p1-r0	—
Alpine v3.12	bind	9.12.2_p1-r0	—
Alpine v3.11	bind	9.12.2_p1-r0	—
Alpine v3.10	bind	9.12.2_p1-r0	—
Alpine v3.9	bind	9.12.2_p1-r0	—
Alpine v3.8	bind	9.12.2_p1-r0	—
Alpine v3.7	bind	9.11.4_p1-r0	—
Alpine v3.6	bind	9.11.4_p1-r0	—
Alpine v3.5	bind	9.10.8_p1-r0	—

Amazon Linux

Release	Package	Fixed in	Advisory
Amazon Linux 2	bind +12	32:9.9.4-61.amzn2.1.1	ALAS2-2018-1082

Oracle Linux

Release	Package	Fixed in	Advisory
Oracle Linux 7	bind +13	32:9.9.4-61.el7_5.1	ELSA-2018-2570

Public exploits

Exploit or proof-of-concept code for this vulnerability is publicly available, which lowers the bar for attackers. Treat it as a reason to patch sooner.

Third-party code, not reviewed by us. Public PoCs are sometimes fake or contain malware. Read the code first and run it only in an isolated lab, against systems you are authorised to test.

GitHub 1 repository

sischkg/cve-2018-5740 ★ 3 · Aug 15, 2018

Sources: PoC-in-GitHub, Metasploit Framework, Exploit-DB — updated daily. Only links are listed; no exploit code is hosted here.

Advisories 13

RHSA-2018:2570 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Jul 1, 2026
RHSA-2018:2571 Red Hat Security Advisory: bind security update Red Hat Security Advisories (RHSA) · Jul 1, 2026
USN-3769-1 bind9 vulnerability Ubuntu Security Notices (USN) · Apr 22, 2026
DLA-2807-1 bind9 - security update Debian Security (DSA / DLA) · Mar 9, 2026
DLA-1485-1 bind9 - security update Debian Security (DSA / DLA) · Mar 9, 2026
SUSE-SU-2019:14074-1 Security update for bind SUSE / openSUSE Security Updates · Feb 4, 2026
SUSE-SU-2019:1407-1 Security update for bind SUSE / openSUSE Security Updates · Feb 4, 2026
openSUSE-SU-2019:1533-1 Security update for bind SUSE / openSUSE Security Updates · Feb 4, 2026
SUSE-SU-2019:1449-1 Security update for bind SUSE / openSUSE Security Updates · Feb 4, 2026
SUSE-SU-2019:2502-1 Security update for bind SUSE / openSUSE Security Updates · Feb 4, 2026
WID-SEC-2025-1193 Internet Systems Consortium BIND: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · May 29, 2025
ALAS2-2018-1082 Important: bind security update (Amazon Linux 2) Amazon Linux Security Center (ALAS) · Sep 25, 2018
ELSA-2018-2570 Important: bind security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Aug 27, 2018

References

105055 vdb-entry
[debian-lts-announce] 20180830 [SECURITY] [DLA 1485-1] bind9 security update mailing-list
RHSA-2018:2570 vendor-advisory
RHSA-2018:2571 vendor-advisory
USN-3769-2 vendor-advisory
1041436 vdb-entry
https://security.netapp.com/advisory/ntap-20180926-0003/
https://kb.isc.org/docs/aa-01639
USN-3769-1 vendor-advisory
GLSA-201903-13 vendor-advisory
openSUSE-SU-2019:1533 vendor-advisory
openSUSE-SU-2019:1532 vendor-advisory
https://support.hpe.com/hpsc/doc/public/display?docLocale=en_US&docId=emr_na-hpesbux03927en_us
[debian-lts-announce] 20211102 [SECURITY] [DLA 2807-1] bind9 security update mailing-list

CNA	v3.0	7.5
EUVD	v3.0	7.5