NGINX ngx_mail_proxy_module vulnerability_CVE-2026-28753

3.7 / 10

LOW

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Description

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.

Basic Information

ID CVE-2026-28753

Source f5

Published Mar 24, 2026 at 14:13

Modified Mar 24, 2026 at 15:24

Affected Product

Vendor F5

Product NGINX Open Source

Version 1.29.0

Affected Versions F5 NGINX Open Source 1.29.0
F5 NGINX Open Source 0.6.27
F5 NGINX Plus R36
F5 NGINX Plus R35
F5 NGINX Plus R34
F5 NGINX Plus R33
F5 NGINX Plus R32

CWE Classification

CWE-93

References

my.f5.com /manage/s/article/K000160367

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