Critical Security Flaw in REST Package: Weak Random Number Generation in PKCE Implementation
Summary
ALSA-2026:47085: Important: rest security update. Affects rest versions < 0.9.1-11.el10_2.1. Fixed in 0.9.1-11.el10_2.1. How to fix ↓
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Background
The 'rest' package is a library designed for seamless access to RESTful web services, enabling developers to interact with APIs efficiently. It is widely utilized in various applications for its simplicity and effectiveness in handling HTTP requests and responses. However, a recently identified vulnerability has raised concerns regarding its security, particularly in the context of the PKCE (Proof Key for Code Exchange) implementation, which is crucial for secure OAuth 2.0 flows.
Vulnerability Detail
The vulnerability stems from weak random number generation in the PKCE implementation of the 'rest' package, identified as CVE-2026-16615. This flaw could allow attackers to predict the random values used in the authentication process, potentially leading to unauthorized access to sensitive resources. The ramifications of this vulnerability are significant, as it undermines the integrity of the authentication mechanism, exposing applications to various security threats.
How To Fix
Minimum fixed version
0.9.1-11.el10_2.1
This is the first release that contains the fix.
sudo dnf update restTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, consider implementing additional security measures such as rate limiting and monitoring for unusual authentication attempts. However, the best course of action is to apply the patch as soon as it is available.
Conclusion
The identified vulnerability in the 'rest' package poses a significant security risk due to weak random number generation in its PKCE implementation. It is crucial for developers and system administrators to update their packages promptly to the patched version to safeguard their applications against potential attacks. Utilizing tools like Vulert can aid in monitoring and managing open-source vulnerabilities effectively.
See every vulnerability recorded for rest →
FAQ
The vulnerability involves weak random number generation in the PKCE implementation of the 'rest' package, which can lead to potential unauthorized access.
You can use the Vulert playground at Vulert Scanner to check if your application is impacted by this vulnerability without needing to sign up.
If exploited, this vulnerability could allow attackers to bypass authentication mechanisms, leading to unauthorized access to sensitive data and resources.
Yes, a patch is available. Update the 'rest' and 'rest-devel' packages to version 0.9.1-11.el10_2.1 to mitigate the risk.
PKCE (Proof Key for Code Exchange) is an extension to OAuth 2.0 that enhances security for public clients by preventing authorization code interception attacks.
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