CVE-2026-28753

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 v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://my.f5.com/manage/s/article/K000160367	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:f5:nginx_plus:r32:p1::::::
	cpe:2.3:a:f5:nginx_plus:r32:p2::::::
	cpe:2.3:a:f5:nginx_plus:r32:p3::::::
	cpe:2.3:a:f5:nginx_plus:r32:p4::::::
	cpe:2.3:a:f5:nginx_plus:r33:::::::*
	cpe:2.3:a:f5:nginx_plus:r33:p1::::::
	cpe:2.3:a:f5:nginx_plus:r33:p2::::::
	cpe:2.3:a:f5:nginx_plus:r33:p3::::::
	cpe:2.3:a:f5:nginx_plus:r34:::::::*
	cpe:2.3:a:f5:nginx_plus:r34:p1::::::
	cpe:2.3:a:f5:nginx_plus:r34:p2::::::
	cpe:2.3:a:f5:nginx_plus:r35:::::::*
	cpe:2.3:a:f5:nginx_plus:r35:p1::::::
	cpe:2.3:a:f5:nginx_plus:r36:::::::*
	cpe:2.3:a:f5:nginx_plus:r36:p1::::::
	cpe:2.3:a:f5:nginx_plus:r36:p2::::::

Configuration 2 (hide)

OR	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::
	cpe:2.3:a:f5:nginx_open_source::::::::

History

No history.

Information

Published : 2026-03-24 15:16

Updated : 2026-03-26 21:15

NVD link : CVE-2026-28753

Mitre link : CVE-2026-28753

CVE.ORG link : CVE-2026-28753

JSON object : View

Products Affected

f5

nginx_plus
nginx_open_source

CWE

CWE-93

Improper Neutralization of CRLF Sequences ('CRLF Injection')

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