How severe is CVE-2023-26437?

CVE-2023-26437 has a CVSS 3.x base score of 3.4, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2023-26437 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-26437?

CVE-2023-26437 affects Powerdns Recursor. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-26437?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2023-26437 published?

CVE-2023-26437 was published on 2023-04-04 and last updated on 2026-06-17.

CVE-2023-26437

CVE-2023-26437 is a low-severity vulnerability in Powerdns Recursor with a CVSS 3.x base score of 3.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: Low (CVSS 3.x base score 3.4)
EPSS exploit prediction: 1% (44th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-400
Affected product: Powerdns Recursor
Published: 2023-04-04
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2023-26437?: 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.
How severe is CVE-2023-26437?: CVE-2023-26437 has a CVSS 3.x base score of 3.4, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2023-26437 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (44th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-26437?: CVE-2023-26437 affects Powerdns Recursor. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-26437?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-26437 published?: CVE-2023-26437 was published on 2023-04-04 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*

More vulnerabilities in Powerdns Recursor

CVE-2009-4009 — Critical (CVSS 10.0): Buffer overflow in PowerDNS Recursor before 3.1.7.2 allows remote attackers to cause a denial of service (daemon crash)…
CVE-2020-10030 — High (CVSS 8.8): An issue has been found in PowerDNS Recursor 4.1.0 up to and including 4.3.0. It allows an attacker (with enough…
CVE-2025-59023 — High (CVSS 8.2): Crafted delegations or IP fragments can poison cached delegations in Recursor.
CVE-2019-3806 — High (CVSS 8.1): An issue has been found in PowerDNS Recursor versions after 4.1.3 before 4.1.9 where Lua hooks are not properly applied…
CVE-2015-5470 — High (CVSS 7.8): The label decompression functionality in PowerDNS Recursor before 3.6.4 and 3.7.x before 3.7.3 and Authoritative (Auth)…
CVE-2015-1868 — High (CVSS 7.8): The label decompression functionality in PowerDNS Recursor 3.5.x, 3.6.x before 3.6.3, and 3.7.x before 3.7.2 and…

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