CVE-2026-28753

CWE-939 documents9 sources
Severity
6.3MEDIUM
EPSS
0.0%
top 93.57%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
2
F5 Nginx Open SourceF5 Nginx Plus
Timeline
PublishedMar 24

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.

CVSS 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

Affected Packages5 packages

▶CVEListV5f5/nginx_open_source0.6.27 — 1.28.3+1
▶NVDf5/nginx_open_source1.0.0 — 1.28.3+2
▶CVEListV5f5/nginx_plusR36 — R36 P3+4
▶NVDf5/nginx_plus5 versions+4
▶Debiannginx< 1.28.3-1

🔴Vulnerability Details

3
GHSA
GHSA-ggr6-fmr8-2m8g: 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 respons↗2026-03-24
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OSV
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 respons↗2026-03-24
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CVEList
NGINX ngx_mail_proxy_module vulnerability↗2026-03-24
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📋Vendor Advisories

4
Red Hat
NGINX: NGINX Plus: NGINX Open Source: NGINX Plus and NGINX Open Source: Request manipulation via header injection in SMTP upstream requests↗2026-03-24
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F5
CVE-2026-28753: NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_module module due to the improper handling...↗2026-03-24
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Microsoft
NGINX ngx_mail_proxy_module vulnerability↗2026-03-10
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Debian
CVE-2026-28753: nginx - NGINX Plus and NGINX Open Source have a vulnerability in the ngx_mail_smtp_modul...↗2026
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🕵️Threat Intelligence

1
Wiz
CVE-2026-28753 Impact, Exploitability, and Mitigation Steps | Wiz↗
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