CVE-2026-27853

Out-of-bounds write when rewriting large DNS packets

Published Mar 31, 2026 CVSS 3.1 · 5.9 Medium EPSS < 1% KEV · Not listed
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

Source ID Title
Debian DSA Debian DSA DSA-6235-1 dnsdist security update
History
Type Values Removed Values Added
CPEs cpe:2.3:a:powerdns:dnsdist:*:*:*:*:*:*:*:*
Type Values Removed Values Added
First Time appeared Powerdns
Powerdns dnsdist
Vendors & Products Powerdns
Powerdns dnsdist
Type Values Removed Values Added
Weaknesses CWE-787
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
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.
Title Out-of-bounds write when rewriting large DNS packets
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
OX
Published
Updated
Mar 31, 2026, 1:17 PM
Reserved
Feb 24, 2026, 8:46 AM
Status
Analyzed
Published
Mar 31, 2026, 12:16 PM
Modified
Jul 25, 2026, 10:10 AM