vulnerability
FreeBSD: VID-0882f019-bd60-11eb-9bdd-8c164567ca3c (CVE-2021-23017): NGINX -- 1-byte memory overwrite in resolver
| Severity | CVSS | Published | Added | Modified |
|---|---|---|---|---|
| 7 | (AV:N/AC:M/Au:N/C:P/I:P/A:P) | May 25, 2021 | Nov 4, 2022 | Mar 25, 2026 |
Severity
7
CVSS
(AV:N/AC:M/Au:N/C:P/I:P/A:P)
Published
May 25, 2021
Added
Nov 4, 2022
Modified
Mar 25, 2026
Description
NGINX team reports: 1-byte memory overwrite might occur during DNS server response processing if the "resolver" directive was used, allowing an attacker who is able to forge UDP packets from the DNS server to cause worker process crash or, potentially, arbitrary code execution.
Solutions
freebsd-upgrade-package-nginxfreebsd-upgrade-package-nginx-devel
Rapid7 Labs
2026 Global Threat Landscape Report
The predictive window has collapsed. Exploitation follows disclosure in days. See how attackers are accelerating and how to stay ahead.