Out-of-bounds write when rewriting large DNS packets_CVE-2026-27853

5.9 / 10

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

An attacker might be able to trigger an out-of-bounds write by sending crafted DNS responses to a DNSdist using the DNSQuestion:changeName or DNSResponse:changeName methods in custom Lua code. In some cases the rewritten packet might become larger than the initial response and even exceed 65535 bytes, potentially leading to a crash resulting in denial of service.

Basic Information

ID CVE-2026-27853

Source OX

Published Mar 31, 2026 at 12:04

Modified Mar 31, 2026 at 13:17

Affected Product

Vendor PowerDNS

Product DNSdist

Version 1.9.0

Affected Versions PowerDNS DNSdist 1.9.0
PowerDNS DNSdist 2.0.0

CWE Classification

CWE-787

References

www.dnsdist.org /security-advisories/powerdns-advisory-for-dnsdist-2026-02.html

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    "published": "2026-03-31T12:04:23.419Z",
    "modified": "2026-03-31T13:17:25.025Z",
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