Vulnerability · Published Jun 25, 2026 · Assigned by OX
CVE-2026-40011Prometheus denial of service via crafted DNS queries
Low 3.7
In plain English
A low-severity security flaw in DNSdist from PowerDNS. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.2% (higher than 13% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)3.7Low
Exploit odds (30 days)0.2%top 86.7% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
An attacker sending a large number of crafted DNS queries might be able to trigger a dynamic block being inserted with a value causing invalid output to be produced in the prometheus endpoint. The prometheus endpoint will then be rejected by the scraper until the dynamic block expires.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian:12 | dnsdist | no fix listed | DEBIAN-CVE-2026-40011 |
| Debian:13 | dnsdist | 1.9.15-0+deb13u1 | DEBIAN-CVE-2026-40011 |
| Debian:14 | dnsdist | 2.1.0-1 | DEBIAN-CVE-2026-40011 |
| Ubuntu:25.10 | dnsdist | no fix listed | UBUNTU-CVE-2026-40011 |
| Ubuntu:26.04:LTS | dnsdist | no fix listed | UBUNTU-CVE-2026-40011 |
| Ubuntu:26.10 | dnsdist | no fix listed | UBUNTU-CVE-2026-40011 |
Affected products (as reported)
Weakness: CWE-116 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N