Out-of-bounds read in dnsdist - CVE-2026-33599

 

Out-of-bounds read in dnsdist - CVE-2026-33599

Published: April 23, 2026


Vulnerability identifier: #VU126947
CSH Severity: Low
CVSS v4: 2.3 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-33599
CWE-ID: CWE-125
Exploitation vector: Adjecent network
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to out-of-bounds read in service discovery when processing crafted SVCB responses. A remote attacker can send a crafted SVCB response to cause a denial of service.

Exploitation requires DDR upgrade to be enabled via the autoUpgrade or auto_upgrade settings.


Affected software

dnsdist
Debian Linux
Fedora
dnsdist (Debian package)
dnsdist

How to mitigate CVE-2026-33599

Install security update from vendor's website.

dnsdist - addressed in versions 1.9.13, 2.0.4
dnsdist (Debian package) - update to 1.9.14-0+deb13u1
dnsdist - update to 2.0.6-1.el10_2

External References

Related Security Bulletins