CRLF Injection Affecting nginx-mod-mail package, versions *


Severity

Recommended
0.0
low
0
10

Based on CentOS security rating.

Threat Intelligence

EPSS
0.26% (17th percentile)

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  • Snyk IDSNYK-CENTOS8-NGINXMODMAIL-15799743
  • published28 Mar 2026
  • disclosed24 Mar 2026

Introduced: 24 Mar 2026

CVE-2026-28753  (opens in a new tab)
CWE-93  (opens in a new tab)

How to fix?

There is no fixed version for Centos:8 nginx-mod-mail.

NVD Description

Note: Versions mentioned in the description apply only to the upstream nginx-mod-mail package and not the nginx-mod-mail package as distributed by Centos. See How to fix? for Centos:8 relevant fixed versions and status.

NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling of CRLF sequences in DNS responses. This allows an attacker-controlled DNS server to inject arbitrary headers into SMTP upstream requests, leading to potential request manipulation. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

CVSS Base Scores

version 3.1