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Fencer Vulns
high 7.5

CVE-2021-36754 in the critical feed json

PowerDNS Authoritative Server 4.5.0 before 4.5.1 allows anybody to crash the process by sending a specific query (QTYPE 65535) that causes…

published 2021-07-27 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-23342

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
64.9%
EPSS 64.9% chance of exploitation in 30 days, percentile 99.2%
public exploits
0
none known, plus a Nuclei check

Summary

PowerDNS Authoritative Server 4.5.0 before 4.5.1 allows anybody to crash the process by sending a specific query (QTYPE 65535) that causes an out-of-bounds exception.

Patch / fix

  • powerdns authoritative_server 4.5.1
  • pdns openSUSE Tumbleweed 4.5.1-1.5

opensuse advisories openSUSE-SU-2024:11156-1

  • pdns Alpine 3.24, Alpine 3.23, Alpine 3.22 +7 more 4.5.1-r0

alpine advisories ALPINE-CVE-2021-36754

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • powerdns Arch Linux 4.5.1-1

arch linux advisories AVG-2222

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-2021-36754 updated cvss 7.5

pdns: specific query crashes Authoritative Server

  • 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

Exploit prediction

64.86% chance of exploitation in the next 30 days, higher than 99.2% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • Nuclei template PowerDNS Authoritative Server - Denial of Service nuclei detection template

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

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.