Vulnerability · Published Apr 22, 2026 · Assigned by OX
CVE-2026-33596TCP backend stream ID overflow
Low 3.1
In plain English
A low-severity integer overflow 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 6% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)3.1Low
Exploit odds (30 days)0.2%top 93.6% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
A client might theoretically be able to cause a mismatch between queries sent to a backend and the received responses by sending a flood of perfectly timed queries that are routed to a TCP-only or DNS over TLS backend.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine:v3.23 | dnsdist | 2.0.4-r0 | ALPINE-CVE-2026-33596 |
| Alpine:v3.24 | dnsdist | 2.0.4-r0 | ALPINE-CVE-2026-33596 |
| Debian:12 | dnsdist | no fix listed | DEBIAN-CVE-2026-33596 |
| Debian:13 | dnsdist | 1.9.14-0+deb13u1 | DEBIAN-CVE-2026-33596 |
| Debian:14 | dnsdist | 2.0.4-1 | DEBIAN-CVE-2026-33596 |
| Ubuntu:25.10 | dnsdist | no fix listed | UBUNTU-CVE-2026-33596 |
| Ubuntu:26.04:LTS | dnsdist | no fix listed | UBUNTU-CVE-2026-33596 |
| Ubuntu:26.10 | dnsdist | no fix listed | UBUNTU-CVE-2026-33596 |
Affected products (as reported)
Weakness: CWE-190 · Vector: CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L