Moderate Vulnerability in coreutils Package: Denial of Service and Information Disclosure
Summary
ALSA-2026:67886: Moderate: coreutils security update. Affects coreutils versions < 9.5-8.el10_2.1. Fixed in 9.5-8.el10_2.1. How to fix ↓
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Background
The coreutils package is a collection of essential utilities for managing files, text, and system processes in Unix-like operating systems. It combines functionalities from the previously separate GNU fileutils, sh-utils, and textutils packages, providing users with a robust set of tools for file manipulation and system management. However, recent vulnerabilities have been identified that could compromise the integrity and availability of systems utilizing this package.
Vulnerability Detail
The coreutils package has been found to contain vulnerabilities that could lead to Denial of Service (DoS) and information disclosure. Specifically, the uniq command is susceptible to an out-of-bounds read when processing multibyte input, which could allow attackers to exploit this flaw to crash the application or leak sensitive information. Additionally, the unexpand command can be manipulated through crafted tab stop values, leading to further denial of service scenarios. These vulnerabilities are tracked under CVE-2026-56391 and CVE-2026-56392, respectively.
How To Fix
Minimum fixed version
9.5-8.el10_2.1
This is the first release that contains the fix.
sudo dnf update coreutilsTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, users can avoid using the uniq and unexpand commands with untrusted input until the package is updated. This can help mitigate the risk of exploitation while waiting for the official patch.
Conclusion
The coreutils package has been identified with moderate vulnerabilities that could lead to Denial of Service and information disclosure. It is crucial for users to update to the patched version to safeguard their systems. Temporary workarounds are available, but updating is the best course of action.
See every vulnerability recorded for coreutils →
FAQ
Coreutils is a package that contains essential command-line utilities for file manipulation, text processing, and system management in Unix-like operating systems.
The vulnerabilities include a Denial of Service and information disclosure via out-of-bounds read in the uniq command and a Denial of Service via crafted tab stop values in the unexpand command.
You can check if your application is affected by using the Vulert playground at Vulert Scanner, which allows you to monitor and alert for open-source vulnerabilities without requiring installation.
If an immediate update is not possible, avoid using the affected commands with untrusted input as a temporary workaround to reduce the risk of exploitation.
More information can be found on the CVE pages for CVE-2026-56391 and CVE-2026-56392, which provide detailed insights into the vulnerabilities and their impacts.
Related vulnerabilities
Recent vulnerabilities recorded for coreutils.
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