CVE-2010-3477 in Linux
Summary
by MITRE
The tcf_act_police_dump function in net/sched/act_police.c in the actions implementation in the network queueing functionality in the Linux kernel before 2.6.36-rc4 does not properly initialize certain structure members, which allows local users to obtain potentially sensitive information from kernel memory via vectors involving a dump operation. NOTE: this vulnerability exists because of an incomplete fix for CVE-2010-2942.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 12/29/2024
The vulnerability described in CVE-2010-3477 represents a critical information disclosure flaw within the Linux kernel's traffic control subsystem. This issue affects the tcf_act_police_dump function located in net/sched/act_police.c, which is part of the network queueing functionality implementation. The flaw manifests when the kernel processes dump operations related to traffic control actions, specifically in the police action module that enforces bandwidth limiting and traffic shaping policies. The vulnerability stems from improper initialization of structure members during the dump operation, creating a potential information leak that could expose sensitive kernel memory contents to local attackers.
The technical nature of this vulnerability aligns with CWE-1286, which addresses improper initialization of structure members, and represents a classic case of information exposure through uninitialized memory. When the tcf_act_police_dump function executes, it fails to properly initialize certain structure members before populating them with data from kernel memory. This incomplete initialization creates a scenario where residual data from previous operations or kernel memory allocation remains in the structure fields, effectively leaking kernel memory contents to userspace processes. The vulnerability is particularly concerning because it occurs during dump operations, which are legitimate administrative functions used to query and display network traffic control configurations, making the information leak an indirect consequence of normal kernel operations rather than a result of malicious input processing.
From an operational perspective, this vulnerability provides local users with access to potentially sensitive kernel memory information that could include cryptographic keys, network credentials, or other confidential data stored in kernel memory regions. The impact extends beyond simple information disclosure as the leaked memory contents might contain patterns or structures that could aid attackers in developing more sophisticated exploits. The vulnerability's persistence across kernel versions until 2.6.36-rc4 indicates that it was not properly addressed in the initial fix for CVE-2010-2942, suggesting a complex interaction between the traffic control subsystem and memory management that required careful handling. This incomplete remediation approach demonstrates the challenges in patching kernel-level vulnerabilities where the root cause involves complex data structures and memory management interactions.
The attack vector for this vulnerability requires local system access, making it a privilege escalation concern rather than a remote exploit. However, the potential for information leakage means that attackers with low-privilege accounts could gain insights into kernel memory layouts, which could be valuable for developing more advanced attacks against the system. The vulnerability's classification under the ATT&CK framework would fall under privilege escalation techniques, specifically leveraging kernel memory disclosure to gain deeper system insights. Organizations should implement immediate mitigations including kernel updates to versions 2.6.36-rc4 or later, which contain proper initialization fixes for the affected structure members. Additionally, monitoring for unusual dump operations or unauthorized access to network traffic control interfaces could help detect potential exploitation attempts, while system hardening measures such as restricting local user access to network administration tools can reduce the attack surface for this particular vulnerability.