ISC BIND 9.8.5 < 9.11.31 / 9.9.3 < 9.11.31 / 9.9.3-S1 < 9.11.31-S1 / 9.12.0 < 9.16.15 / 9.16.8-S1 < 9.16.15-S1 / 9.17.0 < 9.17.12 Assertion Failure (CVE-2021-25214)

medium Nessus Plugin ID 149320


The remote name server is affected by an assertion failure vulnerability vulnerability.


The version of ISC BIND installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the CVE-2021-25214 advisory.

- In BIND 9.8.5 -> 9.8.8, 9.9.3 -> 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 9 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 malformed IXFR triggering the flaw described above, the named process will terminate due to a failed assertion the next time the transferred secondary zone is refreshed. (CVE-2021-25214)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Upgrade to ISC BIND version 9.11.31 / 9.11.31-S1 / 9.16.15 / 9.16.15-S1 / 9.17.12 or later.

See Also

Plugin Details

Severity: Medium

ID: 149320

File Name: bind9_91712.nasl

Version: 1.3

Type: remote

Family: DNS

Published: 5/6/2021

Updated: 5/13/2021

Configuration: Enable paranoid mode

Risk Information


Risk Factor: Low

Score: 3.6


Risk Factor: Medium

Base Score: 4

Temporal Score: 3

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:P

CVSS Score Source: CVE-2021-25214


Risk Factor: Medium

Base Score: 6.5

Temporal Score: 5.7

Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:isc:bind

Required KB Items: bind/version, Settings/ParanoidReport

Exploit Ease: No known exploits are available

Patch Publication Date: 4/28/2021

Vulnerability Publication Date: 4/28/2021

Reference Information

CVE: CVE-2021-25214