CVE-2026-27853

Out-of-bounds write when rewriting large DNS packets

Medium · published March 31, 2026

CVSS v3.1
5.9
EPSS
2%
Percentile
74.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.9 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
CVSS v4.0
Not supplied
EPSS
0.01503 · 74.1th percentile
Published
2026-03-31T12:04Z
EPSS history
Timeline
  • 31 MAR 12:04Z
    Out-of-bounds write when rewriting large DNS packets
    cvelistv5