Skip to content
Fencer Vulns
low 3.1

CVE-2026-33596 json

TCP backend stream ID overflow

published 2026-04-22 6 mo ago modified 2026-10-26 13 d ago also EUVD-2026-24935

cvss
3.1
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 6%
public exploits
0
none known

Summary

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.

Patch / fix

  • PowerDNS DNSdist 1.9.13, 2.0.4
  • dnsdist Debian 13 1.9.14-0+deb13u1
  • dnsdist Debian 14 2.0.4-1

debian advisories DEBIAN-CVE-2026-33596

  • dnsdist SLES for SAP applications 16.0, SLES 16.0 1.9.13-160000.1.1

suse advisories SUSE-SU-2026:22319-1

  • dnsdist openSUSE Leap 16.0 1.9.13-160000.1.1
  • dnsdist openSUSE Tumbleweed 2.0.5-1.1

opensuse advisories openSUSE-SU-2026:21015-1openSUSE-SU-2026:10632-1

  • dnsdist Alpine 3.24, Alpine 3.23 2.0.4-r0

alpine advisories ALPINE-CVE-2026-33596

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-33596 updated cvss 6.5

dnsdist: TCP backend stream ID overflow

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
6 mo ago

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 6% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 3.1 CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
NVD 3.1 6.5 CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • PowerDNS DNSdist

Classification

Weakness
  • CWE-190 Integer Overflow or Wraparound

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.