Critical Arbitrary Code Execution Vulnerability in nginx Package
Summary
ALSA-2026:18063: Critical: nginx security update. Affects nginx versions < 2:1.26.3-2.el10_1.2. Fixed in 2:1.26.3-2.el10_1.2. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
Background
nginx is a high-performance web and proxy server that supports HTTP and other protocols, designed for high concurrency, performance, and low memory usage. It is widely used for serving static content, load balancing, and as a reverse proxy. However, a critical vulnerability has been identified that could allow attackers to execute arbitrary code, compromising the integrity and security of systems running affected versions.
Vulnerability Detail
The vulnerability, identified as CVE-2026-42945, allows for arbitrary code execution due to improper handling of certain requests. This could lead to unauthorized access, data breaches, and potential control over the affected server. The vulnerability originates from flaws in the nginx codebase that fail to adequately validate input, making it susceptible to crafted requests that exploit these weaknesses.
How To Fix
Minimum fixed version
2:1.26.3-2.el10_1.2
This is the first release that contains the fix.
sudo dnf update nginxTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, you can restrict access to the nginx server by implementing firewall rules or limiting the IP addresses that can connect to the server. However, this is not a permanent solution and updating to the patched version is strongly recommended.
Conclusion
The nginx package has a critical vulnerability (CVE-2026-42945) that allows for arbitrary code execution. It is essential to update to the patched version 2:1.26.3-2.el10_1.2 to mitigate the risks associated with this vulnerability. Implementing temporary workarounds can help, but they are not substitutes for applying the necessary updates.
See every vulnerability recorded for nginx →
FAQ
CVE-2026-42945 is a critical vulnerability in the nginx package that allows for arbitrary code execution, potentially compromising server security.
You can check if your nginx installation is affected by using tools like Vulert, which monitors open-source vulnerabilities in your software.
If immediate updates are not possible, consider implementing firewall rules to restrict access as a temporary measure until you can apply the patch.
Versions prior to 2:1.26.3-2.el10_1.2 are affected by this vulnerability. It is crucial to update to the fixed version.
More information can be found on the CVE page for CVE-2026-42945 and the official nginx documentation.
Related vulnerabilities
Recent vulnerabilities recorded for nginx.
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
