F5-K000160367: Low severity F5 NGINX Plus vulnerability

Published Mar 24, 2026
·
Updated

NGINX Plus and NGINX Open Source have a vulnerability in the ngxmailsmtpmodule 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.

Affected Software

3 affected componentsFixes available
F5 NGINX Plus=32
36
F5 NGINX Open Source>=1.0.0<=1.29.6
1.29.71.28.3
F5 NGINX Open Source>=0.6.27<=0.9.7

Event History

Mar 24, 2026
Advisory Published
via F5·01:15 PM
Data Sourced
via F5·01:15 PM
DescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of F5-K000160367?

The severity of F5-K000160367 is considered high due to potential request manipulation risks.

2

How do I fix F5-K000160367?

To fix F5-K000160367, upgrade to NGINX Plus version 36 or NGINX Open Source version 1.29.7 or higher.

3

Which products are affected by F5-K000160367?

F5-K000160367 affects NGINX Plus version 32 and NGINX Open Source versions from 1.0.0 to 1.29.6 and from 0.6.27 to 0.9.7.

4

What kind of attacks does F5-K000160367 open up to?

F5-K000160367 can allow attackers to inject arbitrary headers into SMTP requests through manipulated DNS responses.

5

How can I verify if I am vulnerable to F5-K000160367?

You can verify vulnerability to F5-K000160367 by checking your NGINX Plus or NGINX Open Source version against the specified affected versions.

Contact

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