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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2026-28753 Detail

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.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  F5 Networks
CVSS-B 6.3 MEDIUM
Vector:  CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://my.f5.com/manage/s/article/K000160367 F5 Networks

Weakness Enumeration

CWE-ID CWE Name Source
CWE-93 Improper Neutralization of CRLF Sequences ('CRLF Injection') F5 Networks  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2026-28753
NVD Published Date:
03/24/2026
NVD Last Modified:
03/24/2026
Source:
F5 Networks