Rapid7

vulnerability

FreeBSD: VID-eb03714d-79f0-11f0-b4c1-ac5afc632ba3 (CVE-2025-53859): nginx -- worker process memory disclosure

Severity
4
CVSS
(AV:N/AC:M/Au:N/C:P/I:N/A:N)
Published
Aug 15, 2025
Added
Dec 10, 2025
Modified
Mar 25, 2026

Description

F5 reports: NGINX Open Source and NGINX Plus have a vulnerability in the ngx_mail_smtp_module that might allow an unauthenticated attacker to over-read NGINX SMTP authentication process memory; as a result, the server side may leak arbitrary bytes sent in a request to the authentication server. This issue happens during the NGINX SMTP authentication process and requires the attacker to make preparations against the target system to extract the leaked data. The issue affects NGINX only if (1) it is built with the ngx_mail_smtp_module, (2) the smtp_auth directive is configured with method "none," and (3) the authentication server returns the "Auth-Wait" response header.

Solution

freebsd-upgrade-package-nginx-devel
Title
Rapid7 Labs

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