CVE-2026-33598 Out-of-bounds read in cache inspection via Lua

Medium 4.8 Published 22 Apr 2026 Updated 22 Apr 2026

Attackers can trigger out-of-bounds reads in PowerDNS DNSdist via crafted responses and custom Lua code, potentially causing crashes or data leaks.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: Available

What is CVE-2026-33598?

CVE-2026-33598 is a medium-severity memory corruption vulnerability in PowerDNS DNSdist, published on 22 Apr 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

A cached crafted response can cause an out-of-bounds read if custom Lua code calls getDomainListByAddress() or getAddressListByDomain() on a packet cache.

Weakness: CWE-125

Which versions are affected by CVE-2026-33598?

It affects 1 product.

Products include Powerdns Dnsdist.

How do I fix CVE-2026-33598?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-33598 being exploited?

There is no known exploitation of CVE-2026-33598 in the wild and no public exploit code.

Sources

Also known as DEBIAN-CVE-2026-33598, GHSA-vx33-3w38-3rj6, UBUNTU-CVE-2026-33598.