HOMEVULNERABILITIESCVE-2021-25220
MEDIUM

CVE-2021-25220

CWE-444Published: March 23, 2022· Updated: Jun 17, 2026

6.8
CVSS v3.1

Official 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.

NVD Source

Technical Analysis

CVE-2021-25220 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in full integrity compromise (data manipulation), with a CVSS base score of 6.8.

The vulnerability has a "Changed" scope, meaning successful exploitation can impact components beyond the vulnerable component itself — such as the host operating system or adjacent services.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.High
User InteractionNone
ScopeChanged
Impact
ConfidentialityNone
IntegrityHigh
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:N

Affected Vendors & Products

Fedora1 product(s)
fedora
isc1 product(s)
bind
Juniper Networks29 product(s)
junossrx100srx110srx1400srx1500srx210srx220srx240srx240h2srx240msrx300srx320+17
netapp16 product(s)
h300s firmwareh300sh500s firmwareh500sh700s firmwareh700sh300e firmwareh300eh500e firmwareh500eh700e firmwareh700e+4
siemens1 product(s)
sinec ins
Source: NVD CPE · 62 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (20)

https://kb.isc.org/v1/docs/cve-2021-25220Mitigation · Vendor Advisory
https://kb.isc.org/v1/docs/cve-2021-25220Mitigation · Vendor Advisory

Quick Facts

CVE IDCVE-2021-25220
CVSS Score6.8 / 10
SeverityMEDIUM
WeaknessCWE-444
CISA KEVNo
Affected5 vendor(s)
PublishedMar 23, 2022

Related CVEs (CWE-444)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2021-25220 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWatch. CVE data is provided under the NVD usage policy.