CVE-2022-2795Network attack vector

DNS service interruption via unbounded delegation lookups

Published Sep 21, 2022 · Updated Nov 29, 2024

Resource exhaustion in the named resolver in Internet Systems Consortium BIND 9 allows remote attackers to interrupt DNS resolution. The fctx_getaddresses path performs unbounded address-database lookups across NS records in large delegations, consuming excessive processing time. The flaw requires named to provide recursive resolution and sustained unauthenticated query floods can deny legitimate clients timely DNS answers.

CVSS severity5.3
Medium
EPSS probability1.76%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in the named resolver in Internet Systems Consortium BIND 9 allows remote attackers to interrupt DNS resolution. The fctx_getaddresses path performs unbounded address-database lookups across NS records in large delegations, consuming excessive processing time. The flaw requires named to provide recursive resolution and sustained unauthenticated query floods can deny legitimate clients timely DNS answers.

The record

CVE
CVE-2022-2795
Published
Sep 21, 2022
Updated
Nov 29, 2024
Vendor
Internet Systems Consortium
Product
BIND 9
Classifications
T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 21, 2022CVE publishedPublication date reported by the CVE source.
  2. Nov 29, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=9.0.0 <=9.16.32
  2. Affected versionversion=9.16.8 <9.16.32
  3. Affected versionversion=9.19.0 <9.19.4
  4. Affected versionversion=9.9.3 <9.11.37
  5. Affected versionversion=Development Branch 9.19 9.19.0 through versions before 9.19.5
  6. Affected versionversion=Open Source Branch 9.18 9.18.0 through versions before 9.18.7
  7. Affected versionversion=Open Source Branches 9.0 through 9.16 9.0.0 through versions before 9.16.33
  8. Affected versionversion=Supported Preview Branch 9.16-S 9.16.8-S1 through versions before 9.16.33-S1
  9. Affected versionversion=Supported Preview Branches 9.9-S through 9.11-S 9.9.3-S1 through versions up to and including 9.11.37-S1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Internet Systems Consortium · BIND 9version=9.0.0 <=9.16.32; version=9.16.8 <9.16.32; version=9.19.0 <9.19.4; version=9.9.3 <9.11.37; version=Development Branch 9.19 9.19.0 through versions before 9.19.5; version=Open Source Branch 9.18 9.18.0 through versions before 9.18.7; version=Open Source Branches 9.0 through 9.16 9.0.0 through versions before 9.16.33; version=Supported Preview Branch 9.16-S 9.16.8-S1 through versions before 9.16.33-S1; version=Supported Preview Branches 9.9-S through 9.11-S 9.9.3-S1 through versions up to and including 9.11.37-S1

Published CVSS scores

5.3Internet Systems ConsortiumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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