Division by zero in dnsdist - CVE-2026-33593
Published: April 23, 2026
Vulnerability identifier: #VU126953
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-33593
CWE-ID: CWE-369
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: PowerDNS.COM B.V.
Affected software:
dnsdist
dnsdist
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to divide-by-zero in DNSCrypt query processing when parsing a crafted DNSCrypt query. A remote attacker can send a crafted DNSCrypt query to cause a denial of service.
How to mitigate CVE-2026-33593
Install security update from vendor's website.