ISC BIND Malformed IXFR DoS (CVE-2021-25214)

medium Nessus Plugin ID 149212
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Synopsis

The remote name server is affected by a denial of service vulnerability.

Description

According to its self-reported version, the ISC Bind present on the remote host is affected by a denial of service vulnerability:

- Incremental zone transfers (IXFR) provide a way of transferring changed portion(s) of a zone between servers. An IXFR stream containing SOA records with an owner name other than the transferred zone's apex may cause the receiving named server to inadvertently remove the SOA record for the zone in question from the zone database. When a vulnerable version of named receives a malformed IXFR triggering the flaw, the named process will terminate due to a failed assertion the next time the transferred secondary zone is refreshed.

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

Solution

Upgrade to the patched release most closely related to your current version of BIND.

See Also

https://kb.isc.org/docs/cve-2021-25214

Plugin Details

Severity: Medium

ID: 149212

File Name: bind9_91712_cve-2021-25214.nasl

Version: 1.3

Type: remote

Family: DNS

Published: 4/30/2021

Updated: 5/13/2021

Dependencies: bind_version.nasl

Configuration: Enable paranoid mode

Risk Information

CVSS Score Source: CVE-2021-25214

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 4

Temporal Score: 3

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

Temporal Vector: E:U/RL:OF/RC:C

CVSS v3

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: 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

IAVA: 2021-A-0206