Vulnerability · Published Apr 29, 2021 · Assigned by isc

CVE-2021-25215An assertion check can fail while answering queries for DNAME records that require the DNAME to be processed to resolve itself

High 7.5

In plain English

A high-severity security flaw in BIND9 from ISC. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 11.7% (higher than 96% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)11.7%top 3.9% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Alpine:v3.20	bind	9.16.15-r0	ALPINE-CVE-2021-25215
Alpine:v3.21	bind	9.16.15-r0	ALPINE-CVE-2021-25215
Alpine:v3.22	bind	9.16.15-r0	ALPINE-CVE-2021-25215
Alpine:v3.23	bind	9.16.15-r0	ALPINE-CVE-2021-25215
Alpine:v3.24	bind	9.16.15-r0	ALPINE-CVE-2021-25215
Debian:12	bind9	1:9.16.15-1	DEBIAN-CVE-2021-25215
Debian:13	bind9	1:9.16.15-1	DEBIAN-CVE-2021-25215
Debian:14	bind9	1:9.16.15-1	DEBIAN-CVE-2021-25215
Rocky Linux:8	bind	2:9.11.26-4.el8_4	RLSA-2021:1989

Affected products (as reported)

Vendor	Product	Versions
ISC	BIND9	Open Source Branches 9.0 through 9.11 9.0.0 through versions before 9.11.30Open Source Branches 9.12 through 9.16 9.12.0 through versions before 9.16.14Supported Preview Branches 9.9-S through 9.11-S 9.9.3-S1 through versions before 9.11.30-S1Supported Preview Branch 9.16-S 9.16.8-S1 through versions before 9.16.14-S1Development Branch 9.17 9.17.0 through versiosn before 9.17.12

References

https://kb.isc.org/v1/docs/cve-2021-25215 x_refsource_CONFIRM
[oss-security] 20210428 ISC discloses three BIND vulnerabilities (CVE-2021-25214, CVE-2021-25215, and CVE-2021-25216) mailing-list, x_refsource_MLIST
[oss-security] 20210429 Re: ISC discloses three BIND vulnerabilities (CVE-2021-25214, CVE-2021-25215, and CVE-2021-25216) mailing-list, x_refsource_MLIST
[oss-security] 20210429 Re: ISC discloses three BIND vulnerabilities (CVE-2021-25214, CVE-2021-25215, and CVE-2021-25216) mailing-list, x_refsource_MLIST
[oss-security] 20210429 Re: ISC discloses three BIND vulnerabilities (CVE-2021-25214, CVE-2021-25215, and CVE-2021-25216) mailing-list, x_refsource_MLIST
DSA-4909 vendor-advisory, x_refsource_DEBIAN
[debian-lts-announce] 20210504 [SECURITY] [DLA 2647-1] bind9 security update mailing-list, x_refsource_MLIST
FEDORA-2021-ace61cbee1 vendor-advisory, x_refsource_FEDORA
FEDORA-2021-47f23870ec vendor-advisory, x_refsource_FEDORA
https://www.oracle.com/security-alerts/cpuoct2021.html x_refsource_MISC
https://security.netapp.com/advisory/ntap-20210521-0006/ x_refsource_CONFIRM
https://cert-portal.siemens.com/productcert/pdf/ssa-389290.pdf x_refsource_CONFIRM