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.
History

Tue, 24 Mar 2026 15:15:00 +0000

Type Values Removed Values Added
Description NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_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. 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.

Tue, 24 Mar 2026 14:45:00 +0000

Type Values Removed Values Added
Description NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_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.
Title NGINX ngx_mail_proxy_module vulnerability
Weaknesses CWE-93
References
Metrics cvssV3_1

{'score': 3.7, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N'}

cvssV4_0

{'score': 6.3, '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'}


cve-icon MITRE

Status: PUBLISHED

Assigner: f5

Published:

Updated: 2026-03-24T15:24:34.995Z

Reserved: 2026-03-18T16:06:38.435Z

Link: CVE-2026-28753

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-03-24T15:16:33.560

Modified: 2026-03-24T15:16:33.560

Link: CVE-2026-28753

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.