CVE-2021-25220

DNS forwarders - cache poisoning vulnerability

MEDIUM

6.8

CVSS Score

Published: March 23, 2022 at 12:50 PM UTC

Updated: June 17, 2026 at 03:41 AM UTC

48 products affected across 6 vendorsFedoraJunosH700S Firmware

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Severity

MEDIUM6.8

Exploit prediction

EPSS 3%

Description

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.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Fedora · Fedora Projectrpm

95%

34 35 36

BIND · Isc

95%

v < 9.11.37v < 9.11.37-Sv < 9.16.27v < 9.16.27-S9.11.0 ≤ v < 9.11.379.11.4 ≤ v < 9.11.379.12.0 ≤ v < 9.16.279.16.8 ≤ v < 9.16.279.17.0 ≤ v ≤ 9.18.0Development Branch 9.17 BIND 9.17 all version Open Source Branch 9.18 9.18.0

Affected range stops below 9.11.37, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.11.37-S, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.16.27, so it looks safe — our inference, not a vendor statement

Affected range stops below 9.16.27-S, so it looks safe — our inference, not a vendor statement

Junos · Juniper Networks

95%

v < 19.319.3 19.3 r1-s1 19.3 r2 19.3 r2-s1 19.3 r2-s2 19.3 r2-s3 19.3 r2-s4 19.3 r2-s5 19.3 r2-s6 19.3 r2-s7 19.3 r3 19.3 r3-s1 19.3 r3-s2 19.3 r3-s3 19.3 r3-s4 19.3 r3-s5 19.3 r3-s6 19.4 19.4 r1 19.4 r1-s1 19.4 r1-s2 19.4 r1-s3 19.4 r1-s4 19.4 r2 19.4 r2-s1 19.4 r2-s2 19.4 r2-s3 19.4 r2-s4 19.4 r2-s5 19.4 r2-s6 19.4 r2-s7 19.4 r3 19.4 r3-s1 19.4 r3-s2 19.4 r3-s3 19.4 r3-s4 19.4 r3-s5 19.4 r3-s6 19.4 r3-s7 19.4 r3-s8 20.2 20.2 r1 20.2 r1-s1 20.2 r1-s2 20.2 r1-s3 20.2 r2 20.2 r2-s1 20.2 r2-s2 20.2 r2-s3 20.2 r3 20.2 r3-s1 20.2 r3-s2 20.2 r3-s3 20.2 r3-s4 20.3 20.3 r1 20.3 r1-s1 20.3 r1-s2 20.3 r2 20.3 r2-s1 20.3 r3 20.3 r3-s1 20.3 r3-s2 20.3 r3-s3 20.3 r3-s4 20.4 20.4 r1 20.4 r1-s1 20.4 r2 20.4 r2-s1 20.4 r2-s2 20.4 r3 20.4 r3-s1 20.4 r3-s2 20.4 r3-s3 20.4 r3-s4 21.1 21.1 r1 21.1 r1-s1 21.1 r2 21.1 r2-s1 21.1 r2-s2 21.1 r3 21.1 r3-s1 21.1 r3-s2 21.2 21.2 r1 21.2 r1-s1 21.2 r1-s2 21.2 r2 21.2 r2-s1 21.2 r2-s2 21.2 r3 21.2 r3-s1 21.3 21.3 r1 21.3 r1-s1 21.3 r1-s2 21.3 r2 21.3 r2-s1 21.3 r2-s2 21.3 r3 21.4 21.4 r1 21.4 r1-s1 21.4 r1-s2 21.4 r2 22.1 r1 22.1 r1-s1 22.2 r1

Affected range stops below 19.3, so it looks safe — our inference, not a vendor statement

juniper-srx100 (environment) · juniper-srx110 (environment) · juniper-srx1400 (environment) · juniper-srx1500 (environment) · juniper-srx210 (environment) · juniper-srx220 (environment) · juniper-srx240 (environment) · juniper-srx240h2 (environment) · juniper-srx240m (environment) · juniper-srx300 (environment) · juniper-srx320 (environment) · juniper-srx340 (environment) · juniper-srx3400 (environment) · juniper-srx345 (environment) · juniper-srx3600 (environment) · juniper-srx380 (environment) · juniper-srx4000 (environment) · juniper-srx4100 (environment) · juniper-srx4200 (environment) · juniper-srx4600 (environment) · juniper-srx5000 (environment) · juniper-srx5400 (environment) · juniper-srx550 (environment) · juniper-srx550-hm (environment) · juniper-srx550m (environment) · juniper-srx5600 (environment) · juniper-srx5800 (environment) · juniper-srx650 (environment)

H300E Firmware · NetAppdrupal

95%

All versions

netapp-h300e (same device)

H300S Firmware · NetAppdrupal

95%

All versions

netapp-h300s (same device)

H410C Firmware · NetAppdrupal

95%

All versions

netapp-h410c (same device)