TI-2026-29022 Aliases CVE-2026-40211 GHSA-8mqg-g8g6-fvw6

Denial of service via crafted DoH3 queries

LOW 31CWE-770Published 2026-06-25 · Updated 2026-06-25

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Denial of service
Confidentiality · integrity · availability: None · None · Low
Fix status: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-770.

Summary

An attacker can send crafted DNS over HTTP/3 queries, triggering an exception that prevents some buffer from being freed right away. The buffer will be freed at the end of the QUIC connection, but on some setups it might be possible to open enough concurrent DoH3 streams to trigger an out-of-memory condition, resulting in a denial of service.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.007 53rd percentileScored 2026-11-07

Fix Fixed DNSdist (PowerDNS): 1.9.15, 2.0.7

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

Vendor	Product	Affected versions	Fixed in	Status	Source
PowerDNS	DNSdist	1.9.0 to before 1.9.15; 2.0.0 to before 2.0.7	1.9.15, 2.0.7	Patch available	CNA

DNSdist VendorPowerDNS Affected 1.9.0 to before 1.9.15; 2.0.0 to before 2.0.7 Fixed in 1.9.15, 2.0.7 Patch available CNA

CPE names Threatist (inferred) · 1

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

CPE	Versions	Role	Vendor
cpe:2.3:a:powerdns:dnsdist::::::::	—	—	PowerDNS

cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:* Versions — — ·PowerDNS

Remediation

Fix · CNA DNSdist (PowerDNS) Fixed in 1.9.15, 2.0.7

Fixed in the same release

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

Release · 2026-06-25
PowerDNS DNSdist 1.9.15, 2.0.7
6 records Highest priority Priority LOW 6 LOW
Other records, highest priority first
- TI-2026-29020 Denial of service via IXFR queriesPriority LOW 31
- TI-2026-29021 Out-of-bounds read in SetMacAddrActionPriority LOW 23
- TI-2026-29019 Denial of service via DoH3 queriesPriority LOW 18
Show all 6 records →

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product

Red Hat

Timeline

2026-10-02 Threatist record created from CVE-2026-40211
2026-10-03 Alias added: GHSA-8mqg-g8g6-fvw6

References

Other 1

https://www.dnsdist.org/security-advisories/powerdns-advisory-for-dnsdist-2026-09.html

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