Kernel Samepage Merging Vulnerability in Linux Package: CVE-2015-2877
Summary
DEBIAN-CVE-2015-2877: Kernel Samepage Merging (KSM) in the Linux kernel 2.6.32 through 4.x does not prevent use of a write-timing side channel, which allows guest OS users to defeat the ASLR protection mechanism on other guest OS instances vi... Affects linux versions 5.10.103-1 – 6.9.9-1. No fix is published. 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
Background
The Linux package is a core component of many operating systems, providing essential functionalities such as process management, memory management, and hardware abstraction. It is widely used in various distributions, including Debian. This specific vulnerability affects the Kernel Samepage Merging (KSM) feature, which is designed to optimize memory usage by allowing identical memory pages to be shared among virtual machines. However, this feature can inadvertently expose systems to security risks.
Vulnerability Detail
The vulnerability identified as CVE-2015-2877 arises from the Kernel Samepage Merging (KSM) feature in the Linux kernel versions 2.6.32 through 4.x. It does not adequately prevent the exploitation of a write-timing side channel, enabling malicious users on one guest OS to bypass Address Space Layout Randomization (ASLR) protections on other guest OS instances. This Cross-VM ASL Introspection (CAIN) attack can lead to information disclosure, compromising the security of virtualized environments where multiple untrusted tenants operate.
How To Fix
No fixed version is published for this vulnerability.
Tip — Not sure whether your app is affected? Vulert can check the versions your app actually runs. Scan free →
Workaround
As a temporary workaround, the vendor suggests disabling deduplication features to mitigate the risk associated with this vulnerability. This can be done by modifying the KSM settings in your system's configuration files.
Conclusion
CVE-2015-2877 represents a significant security concern for users of the Linux kernel, particularly in virtualized environments. It is crucial for system administrators to apply the necessary updates and consider workarounds to mitigate risks associated with this vulnerability.
See every vulnerability recorded for linux →
FAQ
CVE-2015-2877 is a vulnerability in the Linux kernel that allows guest OS users to exploit a write-timing side channel, potentially defeating ASLR protections on other guest OS instances.
The vulnerability affects Linux kernel versions from 2.6.32 through 4.x.
You can use tools like Vulert to monitor and alert for open-source vulnerabilities in your software. Visit Vulert Scanner to check if your application is affected without requiring any signup.
If exploited, this vulnerability could allow unauthorized access to sensitive information across virtual machines, compromising the security of multi-tenant environments.
Yes, updating to a patched version of the Linux kernel is the recommended permanent fix for this vulnerability.
References
Related vulnerabilities
Recent vulnerabilities recorded for linux.
