CVE-2011-4917 in Linux
Summary
by MITRE • 04/18/2022
In the Linux kernel through 3.1 there is an information disclosure issue via /proc/stat.
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Analysis
by VulDB Data Team • 08/04/2026
The vulnerability in question involves an information disclosure flaw within the Linux kernel version 3.1 and earlier, specifically affecting the /proc/stat virtual file system interface. This issue arises from improper access controls and data exposure mechanisms that allow unauthorized processes to read sensitive system statistics that should remain restricted. The /proc/stat file contains critical performance metrics including CPU time measurements, context switches, interrupts, and other kernel-level operational data that provides insights into system behavior and resource utilization patterns.
The technical implementation flaw stems from the kernel's handling of permissions and access validation within the proc filesystem subsystem. When processes attempt to read from /proc/stat without proper authorization, the kernel fails to adequately sanitize or restrict access to certain statistical counters that could reveal information about other running processes, system load patterns, or even potential timing-based side-channel attack vectors. This vulnerability operates at the kernel level and affects all Linux systems using versions prior to 3.2, making it particularly concerning given the widespread adoption of these kernel versions in enterprise environments.
The operational impact of this information disclosure vulnerability extends beyond simple data exposure, as the collected statistics could enable attackers to perform sophisticated analysis of system behavior and resource consumption patterns. An attacker with access to /proc/stat could potentially infer information about other processes running on the system, identify system load characteristics, or even develop timing-based attacks that exploit predictable resource usage patterns. The vulnerability particularly affects systems where process isolation is critical, such as multi-tenant environments, cloud deployments, or systems handling sensitive data processing.
From a cybersecurity perspective, this issue aligns with CWE-200, which addresses information exposure through improper access control mechanisms in system interfaces. The vulnerability also maps to ATT&CK technique T1082, which covers system information discovery activities that adversaries often employ to gather intelligence about target systems. This particular vulnerability represents a fundamental flaw in the kernel's privilege separation model and highlights the critical importance of proper access control implementation within core operating system components.
Mitigation strategies for this vulnerability primarily involve upgrading to Linux kernel version 3.2 or later, where the necessary access controls and data sanitization measures have been implemented. System administrators should also consider implementing additional monitoring and access control policies around proc filesystem access, particularly for processes that do not require elevated privileges to read system statistics. The fix typically involves strengthening permission checking mechanisms within the kernel's proc filesystem implementation and ensuring that sensitive statistical data is properly protected from unauthorized access attempts. Organizations should conduct thorough vulnerability assessments to identify systems running affected kernel versions and prioritize remediation efforts based on risk exposure levels.