Read the docs
TI-2026-30689 Aliases CVE-2026-42389GHSA-hrq7-vr6r-5mvq

Reject more queries with invalid header values

Priority LOW 30CWE-20Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · Low · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

This fix provides extra hardening for the 5.4.x branch by doing extra validation of incoming answers from authoritative servers.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00299 22nd percentileScored 2026-11-07
Fix Fixed Recursor (PowerDNS): 5.4.3

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
PowerDNSRecursor5.4.0 to before 5.4.35.4.3Patch availableCNA
  • Recursor VendorPowerDNS Affected 5.4.0 to before 5.4.3 Fixed in 5.4.3 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:*——PowerDNS
  • cpe:2.3:a:powerdns:recursor:*:*:*:*:*:*:*:* Versions — — ·PowerDNS

Remediation

  • Fix · CNA Recursor (PowerDNS) Fixed in 5.4.3

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Release ·

    PowerDNS Recursor 5.4.3

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    Show all 2 records →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42389
  2. 2026-10-03 Alias added: GHSA-hrq7-vr6r-5mvq

References

Other 1

  • TI-2023-27571 Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related… CVSS 3.1HIGH 7.5
  • TI-2023-27773 The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance… CVSS 3.1HIGH 7.5
  • TI-2015-01678 The label decompression functionality in PowerDNS Recursor 3.5.x, 3.6.x before 3.6.3, and… CVSS 2.0HIGH 7.8
  • TI-2021-14878 PowerDNS Authoritative Server 4.5.0 before 4.5.1 allows anybody to crash the process by… CVSS 3.1HIGH 7.5
  • TI-2016-04703 PowerDNS (aka pdns) Authoritative Server before 3.4.10 does not properly handle a . CVSS 3.0HIGH 7.5
  • TI-2018-12065 Out-of-bounds read in [UNKNOWN] pdns-recursor CVSS 3.0HIGH 7.5
See all 130 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences