Critical Vulnerability in linux-realtime Package: CVE-2025-21813
Summary
USN-7489-2: linux-realtime vulnerability. Affects linux-realtime versions < 6.11.0-1009.9. Fixed in 6.11.0-1009.9. How to fix ↓
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Background
The linux-realtime package is a version of the Linux kernel optimized for real-time applications, providing low-latency performance and predictable response times. It is widely used in environments where timing is critical, such as audio processing, robotics, and industrial automation. However, a security issue has been identified that could allow an attacker to compromise systems running this kernel version.
Vulnerability Detail
A security issue was discovered in the Linux kernel, specifically in the timer subsystem. This vulnerability, identified as CVE-2025-21813, could potentially allow an attacker to exploit the system, leading to unauthorized access or control. The flaw arises from improper handling of timer events, which could be manipulated to execute arbitrary code or disrupt system operations.
How To Fix
Minimum fixed version
6.11.0-1009.9
This is the first release that contains the fix.
sudo apt-get install --only-upgrade linux-realtimeTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
Currently, there are no specific workarounds mentioned for this vulnerability. The best course of action is to apply the patch as soon as it becomes available.
Conclusion
In summary, the linux-realtime package has a critical vulnerability (CVE-2025-21813) that could allow attackers to compromise systems. It is crucial to update to the patched version 6.11.0-1009.9 to mitigate this risk. Utilizing tools like Vulert can help monitor and alert for vulnerabilities in your software.
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FAQ
CVE-2025-21813 is a security vulnerability in the Linux kernel's timer subsystem that could allow an attacker to compromise the system.
You can use Vulert, which monitors open-source vulnerabilities in your software. By uploading your manifest file, you can check for vulnerabilities without needing to install any software.
If exploited, this vulnerability could allow unauthorized access to the system, potentially leading to data breaches or system control by malicious actors.
Yes, a patch is available in version 6.11.0-1009.9 of the linux-realtime package. It is recommended to update to this version immediately.
You can use services like Vulert to receive real-time alerts for open-source vulnerabilities in your software, ensuring you are always updated on potential risks.
References
Related vulnerabilities
Recent vulnerabilities recorded for linux-realtime.
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