USN-8458-1: nginx vulnerabilities

Publication date

22 June 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 large headers when
proxying HTTP/2 traffic. A remote attacker could use this issue to cause
nginx to crash, resulting in a denial of service, or possibly execute
arbitrary code. The default compiler options for affected releases should
reduce the vulnerability to a denial of service. (CVE-2026-42055)

It was discovered that nginx incorrectly handled character set conversion
under certain circumstances. A remote attacker could possibly use this
issue to obtain sensitive information or cause nginx to crash, resulting in
a denial of service. (CVE-2026-48142)

It was discovered that nginx incorrectly handled large headers when
proxying HTTP/2 traffic. A remote attacker could use this issue to cause
nginx to crash, resulting in a denial of service, or possibly execute
arbitrary code. The default compiler options for affected releases should
reduce the vulnerability to a denial of service. (CVE-2026-42055)

It was discovered that nginx incorrectly handled character set conversion
under certain circumstances. A remote attacker could possibly use this
issue to obtain sensitive information or cause nginx to crash, resulting in
a denial of service. (CVE-2026-48142)

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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