CVE-2023-26437

Deterred spoofing attempts can lead to authoritative servers being marked unavailable

MEDIUM

5.3

CVSS Score

Published: April 4, 2023 at 02:37 PM UTC

Updated: June 17, 2026 at 05:43 AM UTC

1 product affected across 1 vendorRecursor

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Severity

MEDIUM5.3

Exploit prediction

EPSS 0.6%

SSVC

No known exploit

Description

Denial of service vulnerability in PowerDNS Recursor allows authoritative servers to be marked unavailable.This issue affects Recursor: through 4.6.5, through 4.7.4 , through 4.8.3.

Affected

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

Recursor · Powerdns

95%

v ≤ 4.6.5v ≤ 4.7.4v ≤ 4.8.3v < 4.6.64.7.0 ≤ v < 4.7.54.8.0 ≤ v < 4.8.4

Affected range stops below 4.6.6, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.7.5, so it looks safe — our inference, not a vendor statement

Affected range stops below 4.8.4, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2023-02.html

References (3)

Vendor Advisory

Source: [email protected]

https://docs.powerdns.com/recursor/security-advisories/powerdns-advisory-2023-02.html

Source: [email protected]

https://lists.fedoraproject.org/archives/list/[email protected]/message/CN7VMRYKZHG2UDUAK326LXD3JY7NO3LR/

Source: [email protected]

https://lists.fedoraproject.org/archives/list/[email protected]/message/IHPD6SIQOG7245GXFQHPUEI4AZ6Y3KD6/

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

5.3MEDIUM[email protected]

Attack Vector: NETWORK
Complexity: LOW
Privileges: NONE
User Interaction: NONE
Scope: UNCHANGED
Confidentiality: NONE
Integrity: NONE
Availability: LOW

Vector?

Quick Info

StatusMODIFIED

CWE

NVD-CWE-noinfoCWE-400

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