CVE-2026-28753
Fixed in a distro release EPSS <1%CVSS 3.7
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.
Products: F5 NGINX Open Source, F5 NGINX Plus
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Alpine 3.22 | nginx | 1.28.3-r0 |
| Alpine 3.23 | nginx | 1.28.3-r0 |
| Alpine 3.24 | nginx | 1.28.3-r0 |
| Amazon Linux 2023 | nginx | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-all-modules | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-core | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-filesystem | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-devel | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-http-image-filter | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-http-perl | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-http-xslt-filter | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-mail | 1:1.28.3-1.amzn2023.0.1 |
| Amazon Linux 2023 | nginx-mod-stream | 1:1.28.3-1.amzn2023.0.1 |
| Chainguard | nginx-mainline | 1.29.7-r0 |
| Chainguard | nginx-stable | 1.28.3-r0 |
| Debian 12 | nginx | 1.22.1-9+deb12u5 |
| Debian 13 | nginx | 1.26.3-3+deb13u3 |
| Debian 14 | nginx | 1.28.3-1 |
| Red Hat hummingbird 1 | nginx | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-all-modules | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-core | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-filesystem | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-devel | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-http-geoip | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-http-image-filter | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-http-perl | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-http-xslt-filter | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-mail | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-stream | 0:1.30.0-1.hum1 |
| Red Hat hummingbird 1 | nginx-mod-stream-geoip | 0:1.30.0-1.hum1 |
| Ubuntu 22.04 LTS | nginx | 1.18.0-6ubuntu14.10 |
| Ubuntu 24.04 LTS | nginx | 1.24.0-2ubuntu7.7 |
| Ubuntu 25.10 | nginx | 1.28.0-6ubuntu1.2 |
| Ubuntu Pro 14.04 LTS | nginx | 1.4.6-1ubuntu3.9+esm6 |
| Ubuntu Pro 16.04 LTS | nginx | 1.10.3-0ubuntu0.16.04.5+esm7 |
| Ubuntu Pro 18.04 LTS | nginx | 1.14.0-0ubuntu1.11+esm2 |
| Ubuntu Pro 20.04 LTS | nginx | 1.18.0-0ubuntu1.7+esm1 |
| Wolfi | nginx-mainline | 1.29.7-r0 |
| Wolfi | nginx-stable | 1.28.3-r0 |
| openSUSE Tumbleweed | nginx | 1.29.7-1.1 |