CVE-2026-40211 Denial of service via crafted DoH3 queries
MediumCVSS 5.3
EPSS 0.70%
- Published
- Updated
- Exploit status
- No public exploit known
Description
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.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| PowerDNS DNSdist | >= 1.9.0, < 1.9.15 | 1.9.15 |
| PowerDNS DNSdist | >= 2.0.0, < 2.0.7 | 2.0.7 |
| debian/dnsdist(Debian:12) | All versions | No fix listed |
| debian/dnsdist(Debian:12) | = 1.7.3-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.0-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.1-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.2-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.2-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.2-3 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.3-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.3-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.8.3-3 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.10-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.3-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.4-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.5-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.6-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.8-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 1.9.9-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-3 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-4 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-5 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0-6 | No fix listed |
Show 43 more
| Product | Affected versions | Fixed in |
|---|---|---|
| debian/dnsdist(Debian:12) | = 2.0.0~rc1-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0~rc1-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.0~rc2-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.1-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.2-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.3-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.4-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.5-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.5-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.5-3 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.0.6-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.1.0-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.1.0-2 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.1.1-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.1.2-1 | No fix listed |
| debian/dnsdist(Debian:12) | = 2.1.3-1 | No fix listed |
| debian/dnsdist(Debian:13) | < 1.9.15-0+deb13u1 | 1.9.15-0+deb13u1 |
| debian/dnsdist(Debian:13) | = 1.9.10-1 | No fix listed |
| debian/dnsdist(Debian:13) | = 1.9.10-1+deb13u1 | No fix listed |
| debian/dnsdist(Debian:13) | = 1.9.14-0+deb13u1 | No fix listed |
| debian/dnsdist(Debian:14) | < 2.1.0-1 | 2.1.0-1 |
| debian/dnsdist(Debian:14) | = 1.9.10-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-2 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-3 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-4 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-5 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0-6 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0~rc1-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0~rc1-2 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.0~rc2-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.1-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.2-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.3-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.4-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.5-1 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.5-2 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.5-3 | No fix listed |
| debian/dnsdist(Debian:14) | = 2.0.6-1 | No fix listed |
| ubuntu/dnsdist(Ubuntu:22.04) | All versions | No fix listed |
| ubuntu/dnsdist(Ubuntu:24.04) | All versions | No fix listed |
| ubuntu/dnsdist(Ubuntu:26.04) | All versions | No fix listed |
| ubuntu/dnsdist(Ubuntu:26.10) | All versions | No fix listed |
References
- www.dnsdist.org
- Debian Security Tracker CVE-2026-40211 vendor-advisory
- Ubuntu CVE tracker vendor-advisory
- www.cve.org