medium
6.8
CWE
444
Advisory Published
CVE Published
Updated

CVE-2021-25220: DNS forwarders - cache poisoning vulnerability

First published: Wed Mar 16 2022(Updated: )

BIND 9.11.0 -> 9.11.36 9.12.0 -> 9.16.26 9.17.0 -> 9.18.0 BIND Supported Preview Editions: 9.11.4-S1 -> 9.11.36-S1 9.16.8-S1 -> 9.16.26-S1 Versions of BIND 9 earlier than those shown - back to 9.1.0, including Supported Preview Editions - are also believed to be affected but have not been tested as they are EOL. The cache could become poisoned with incorrect records leading to queries being made to the wrong servers, which might also result in false information being returned to clients.

Credit: security-officer@isc.org

Affected SoftwareAffected VersionHow to fix
redhat/bind<32:9.11.4-26.P2.el7_9.13
32:9.11.4-26.P2.el7_9.13
redhat/bind9.16<32:9.16.23-0.9.el8.1
32:9.16.23-0.9.el8.1
redhat/bind<32:9.11.36-5.el8
32:9.11.36-5.el8
redhat/bind<32:9.16.23-5.el9_1
32:9.16.23-5.el9_1
redhat/dhcp<12:4.4.2-17.b1.el9
12:4.4.2-17.b1.el9
redhat/bind<9.11.37
9.11.37
redhat/bind<9.16.27
9.16.27
redhat/bind<9.18.1
9.18.1
ISC BIND>=9.11.0<9.11.37
ISC BIND>=9.11.4<9.11.37
ISC BIND>=9.12.0<9.16.27
ISC BIND>=9.16.8<9.16.27
ISC BIND>=9.17.0<=9.18.0
Fedora=34
Fedora=35
Fedora=36
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h300s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h500s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h700s
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h300e
netapp baseboard management controller h500e firmware
netapp baseboard management controller h500e
netapp baseboard management controller h700e firmware
netapp baseboard management controller h700e
NetApp Baseboard Management Controller Firmware
netapp baseboard management controller h410s
netapp baseboard management controller h410c firmware
netapp baseboard management controller h410c
siemens sinec ins<1.0
siemens sinec ins=1.0
siemens sinec ins=1.0-sp1
Juniper Junos<19.3
Juniper Junos=19.3
Juniper Junos=19.3-r1-s1
Juniper Junos=19.3-r2
Juniper Junos=19.3-r2-s1
Juniper Junos=19.3-r2-s2
Juniper Junos=19.3-r2-s3
Juniper Junos=19.3-r2-s4
Juniper Junos=19.3-r2-s5
Juniper Junos=19.3-r2-s6
Juniper Junos=19.3-r2-s7
Juniper Junos=19.3-r3
Juniper Junos=19.3-r3-s1
Juniper Junos=19.3-r3-s2
Juniper Junos=19.3-r3-s3
Juniper Junos=19.3-r3-s4
Juniper Junos=19.3-r3-s5
Juniper Junos=19.3-r3-s6
Juniper Junos=19.4
Juniper Junos=19.4-r1
Juniper Junos=19.4-r1-s1
Juniper Junos=19.4-r1-s2
Juniper Junos=19.4-r1-s3
Juniper Junos=19.4-r1-s4
Juniper Junos=19.4-r2
Juniper Junos=19.4-r2-s1
Juniper Junos=19.4-r2-s2
Juniper Junos=19.4-r2-s3
Juniper Junos=19.4-r2-s4
Juniper Junos=19.4-r2-s5
Juniper Junos=19.4-r2-s6
Juniper Junos=19.4-r2-s7
Juniper Junos=19.4-r3
Juniper Junos=19.4-r3-s1
Juniper Junos=19.4-r3-s2
Juniper Junos=19.4-r3-s3
Juniper Junos=19.4-r3-s4
Juniper Junos=19.4-r3-s5
Juniper Junos=19.4-r3-s6
Juniper Junos=19.4-r3-s7
Juniper Junos=19.4-r3-s8
Juniper Junos=20.2
Juniper Junos=20.2-r1
Juniper Junos=20.2-r1-s1
Juniper Junos=20.2-r1-s2
Juniper Junos=20.2-r1-s3
Juniper Junos=20.2-r2
Juniper Junos=20.2-r2-s1
Juniper Junos=20.2-r2-s2
Juniper Junos=20.2-r2-s3
Juniper Junos=20.2-r3
Juniper Junos=20.2-r3-s1
Juniper Junos=20.2-r3-s2
Juniper Junos=20.2-r3-s3
Juniper Junos=20.2-r3-s4
Juniper Junos=20.3
Juniper Junos=20.3-r1
Juniper Junos=20.3-r1-s1
Juniper Junos=20.3-r1-s2
Juniper Junos=20.3-r2
Juniper Junos=20.3-r2-s1
Juniper Junos=20.3-r3
Juniper Junos=20.3-r3-s1
Juniper Junos=20.3-r3-s2
Juniper Junos=20.3-r3-s3
Juniper Junos=20.3-r3-s4
Juniper Junos=20.4
Juniper Junos=20.4-r1
Juniper Junos=20.4-r1-s1
Juniper Junos=20.4-r2
Juniper Junos=20.4-r2-s1
Juniper Junos=20.4-r2-s2
Juniper Junos=20.4-r3
Juniper Junos=20.4-r3-s1
Juniper Junos=20.4-r3-s2
Juniper Junos=20.4-r3-s3
Juniper Junos=20.4-r3-s4
Juniper Junos=21.1
Juniper Junos=21.1-r1
Juniper Junos=21.1-r1-s1
Juniper Junos=21.1-r2
Juniper Junos=21.1-r2-s1
Juniper Junos=21.1-r2-s2
Juniper Junos=21.1-r3
Juniper Junos=21.1-r3-s1
Juniper Junos=21.1-r3-s2
Juniper Junos=21.2
Juniper Junos=21.2-r1
Juniper Junos=21.2-r1-s1
Juniper Junos=21.2-r1-s2
Juniper Junos=21.2-r2
Juniper Junos=21.2-r2-s1
Juniper Junos=21.2-r2-s2
Juniper Junos=21.2-r3
Juniper Junos=21.2-r3-s1
Juniper Junos=21.3
Juniper Junos=21.3-r1
Juniper Junos=21.3-r1-s1
Juniper Junos=21.3-r1-s2
Juniper Junos=21.3-r2
Juniper Junos=21.3-r2-s1
Juniper Junos=21.3-r2-s2
Juniper Junos=21.3-r3
Juniper Junos=21.4
Juniper Junos=21.4-r1
Juniper Junos=21.4-r1-s1
Juniper Junos=21.4-r1-s2
Juniper Junos=21.4-r2
Juniper Junos=22.1-r1
Juniper Junos=22.1-r1-s1
Juniper Junos=22.2-r1
Juniper SRX100
Juniper SRX110
Juniper SRX1400
Juniper SRX1500
Juniper SRX210
Juniper SRX220
Juniper SRX240
Juniper SRX240H2
Juniper SRX240M
Juniper SRX300
Juniper SRX320
Juniper SRX340
Juniper SRX3400
Juniper SRX345
Juniper SRX3600
Juniper SRX380
Juniper SRX4000
Juniper SRX4100
Juniper SRX4200
Juniper SRX4600
Junos OS SRX 5000 Series
Juniper SRX5400
Juniper SRX550
Juniper SRX550
Juniper SRX550
juniper srx5600
Juniper SRX5800
Juniper SRX650
netapp h300s firmware
netapp h300s
NetApp H500S Firmware
netapp h500s
netapp h700s firmware
netapp h700s
netapp h300e firmware
netapp h300e
netapp h500e firmware
netapp h500e
netapp h700e firmware
netapp h700e
netapp h410s firmware
netapp h410s
netapp h410c firmware
netapp h410c

Remedy

If applicable, modify your configuration to either remove all forwarding or all possibility of recursion. Depending on your use case, it may be possible to use other zone types to replace forward zones.

Remedy

https://cert-portal.siemens.com/productcert/pdf/ssa-637483.pdf

Remedy

Upgrade to the patched release most closely related to your current version of BIND: BIND 9.11.37 BIND 9.16.27 BIND 9.18.1 BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers. BIND 9.11.37-S1 BIND 9.16.27-S1

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2021-25220?

    CVE-2021-25220 is rated as high severity due to the potential for unauthorized access and exploitation of vulnerable BIND versions.

  • How do I fix CVE-2021-25220?

    To fix CVE-2021-25220, upgrade to the latest patched version of BIND, which are 9.11.37, 9.16.27, or 9.18.1, depending on your distribution.

  • Which versions of BIND are affected by CVE-2021-25220?

    CVE-2021-25220 affects BIND versions from 9.11.0 to 9.11.36, 9.12.0 to 9.16.26, and 9.17.0 to 9.18.0.

  • What are the recommended actions for users running vulnerable versions of BIND due to CVE-2021-25220?

    Users running vulnerable versions should immediately apply updates or install the recommended patches to mitigate the risk associated with CVE-2021-25220.

  • Is CVE-2021-25220 being actively exploited in the wild?

    While there are indicators of this vulnerability being targeted, it is advisable for users to implement updates to minimize security risks.

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