USN-8563-1: nginx vulnerabilities

Publication date

20 July 2026

Overview

Several security issues were fixed in nginx.


Packages

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

Details

It was discovered that nginx incorrectly handled certain map directives
using regex matching and capture variables. A remote attacker could use
this issue to cause nginx to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2026-42533)

It was discovered that nginx had a use-after-free vulnerability in the
ngx_http_ssi_module module when configured with Server-Side Includes,
proxy_pass, and proxy buffering disabled directives. An attacker able to
intercept traffic and control responses from an upstream server could
possibly use this issue to cause nginx to crash, resulting in a denial of
service. (CVE-2026-56434)

It was discovered that nginx incorrectly handled certain requests in the
ngx_http_slice_module module. A remote attacker could possibly use this
issue to obtain sensitive information or cause nginx to crash,...

It was discovered that nginx incorrectly handled certain map directives
using regex matching and capture variables. A remote attacker could use
this issue to cause nginx to crash, resulting in a denial of service, or
possibly execute arbitrary code. (CVE-2026-42533)

It was discovered that nginx had a use-after-free vulnerability in the
ngx_http_ssi_module module when configured with Server-Side Includes,
proxy_pass, and proxy buffering disabled directives. An attacker able to
intercept traffic and control responses from an upstream server could
possibly use this issue to cause nginx to crash, resulting in a denial of
service. (CVE-2026-56434)

It was discovered that nginx incorrectly handled certain requests in the
ngx_http_slice_module module. A remote attacker could possibly use this
issue to obtain sensitive information or cause nginx to crash, resulting
in a denial of service. (CVE-2026-60005)


Update instructions

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

Learn more about how to get the fixes.

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


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