Alerts This Week
Warning Icon 1 1,039
Alerts This Week
Warning Icon 1 1,039

Ubuntu Nginx Important Denial of Service Issues USN-8375-1

ubuntu
Calendar Grey June 3, 2026
Dist Ubuntu Esm H88
Several security issues were addressed in nginx for Ubuntu, impacting various LTS versions and leading to critical threats.
Several security issues were fixed in nginx.

Summary

Several security issues were fixed in nginx.

Software Description:

- nginx: small, powerful, scalable web/proxy server

Details:

It was discovered that the nginx ngx_mail_smtp_module module incorrectly

handled certain memory operations when doing SMTP authentication. This

could possibly result in sensitive information being sent to the

authentication server. (CVE-2025-53859)

It was discovered that nginx incorrectly handled proxying to upstream TLS

servers. An attacker could possibly use this issue to insert plain text

data into the response from an upstream proxied server. (CVE-2026-1642)

It was discovered that the nginx ngx_mail_auth_http_module module

incorrectly handled certain requests. An attacker could possibly use this

issue to cause nginx to crash, resulting in a denial of service.

(CVE-2026-27651)

It was discovered that the nginx ngx_http_dav_module module incorrectly

handled certain destination URIs. An attacker could use this issue to cause

nginx to crash, resulting...

Read the Full Advisory

Topics%20covered

Topics Covered

security advisory denial of service Ubuntu important information exposure nginx

Update Instructions

The problem can be corrected by updating your system to the following
package versions:

Ubuntu 20.04 LTS
  libnginx-mod-http-headers-more-filter  1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  libnginx-mod-http-lua           1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  libnginx-mod-mail               1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  libnginx-mod-nchan              1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  libnginx-mod-rtmp               1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  nginx                           1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  nginx-core                      1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  nginx-extras                    1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  nginx-full                      1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro
  nginx-light                     1.18.0-0ubuntu1.7+esm1
                                  Available with Ubuntu Pro

Ubuntu 18.04 LTS
  libnginx-mod-http-auth-pam      1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-cache-purge   1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-dav-ext       1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-echo          1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-fancyindex    1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-geoip         1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-headers-more-filter  1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-image-filter  1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-lua           1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-ndk           1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-perl          1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-subs-filter   1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-uploadprogress  1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-upstream-fair  1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-http-xslt-filter   1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-mail               1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-nchan              1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-rtmp               1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  libnginx-mod-stream             1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  nginx                           1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  nginx-core                      1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  nginx-extras                    1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  nginx-full                      1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro
  nginx-light                     1.14.0-0ubuntu1.11+esm2
                                  Available with Ubuntu Pro

Ubuntu 16.04 LTS
  nginx                           1.10.3-0ubuntu0.16.04.5+esm7
                                  Available with Ubuntu Pro
  nginx-core                      1.10.3-0ubuntu0.16.04.5+esm7
                                  Available with Ubuntu Pro
  nginx-extras                    1.10.3-0ubuntu0.16.04.5+esm7
                                  Available with Ubuntu Pro
  nginx-full                      1.10.3-0ubuntu0.16.04.5+esm7
                                  Available with Ubuntu Pro
  nginx-light                     1.10.3-0ubuntu0.16.04.5+esm7
                                  Available with Ubuntu Pro

Ubuntu 14.04 LTS
  nginx                           1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-common                    1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-core                      1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-extras                    1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-full                      1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-light                     1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro
  nginx-naxsi                     1.4.6-1ubuntu3.9+esm6
                                  Available with Ubuntu Pro

In general, a standard system update will make all the necessary changes.

References

https://ubuntu.com/security/notices/USN-8375-1

CVE-2025-53859, CVE-2026-1642, CVE-2026-27651, CVE-2026-27654,

CVE-2026-27784, CVE-2026-28753, CVE-2026-32647, CVE-2026-40701,

CVE-2026-42934, CVE-2026-42945, CVE-2026-42946, CVE-2026-9256

Severity
important
Lowest
Low
Medium
High
Critical

Ubuntu Security Notice USN-8375-1

Topics%20covered

Topics Covered

security advisory denial of service Ubuntu important information exposure nginx

Package Information

Get the latest News and Insights

Get the latest Linux and open source security news straight to your inbox.

Your message here