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Fencer Vulns
low 3.4

CVE-2023-26437 json

Deterred spoofing attempts can lead to authoritative servers being marked unavailable

published 2023-04-04 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-30257

cvss
3.4
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.6%
EPSS 0.6% chance of exploitation in 30 days, percentile 48%
public exploits
0
none known

Summary

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.

Patch / fix

  • powerdns recursor 4.6.6, 4.7.5, 4.8.4
  • pdns-recursor Debian 14, Debian 13, Debian 12 4.8.4-1

debian advisories DEBIAN-CVE-2023-26437

  • pdns-recursor openSUSE Tumbleweed 4.8.4-1.1
  • pdns-recursor Package Hub 15 SP5, openSUSE Leap 15.5 4.8.6-bp155.2.3.1
  • pdns-recursor Package Hub 15 SP4, openSUSE Leap 15.4 4.6.6-bp154.2.6.1

opensuse advisories openSUSE-SU-2024:12838-1openSUSE-SU-2024:0048-1openSUSE-SU-2023:0101-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2023-26437 updated cvss 3.4

pdns-recursor: Deterred spoofing attempts can lead to authoritative servers being marked unavailable

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
20 mo ago

Exploit prediction

0.59% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 3.4 CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:N/I:N/A:L
NVD 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

  • PowerDNS Recursor

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.