CVE-2014-6410 in Linux
Summary
by MITRE
The __udf_read_inode function in fs/udf/inode.c in the Linux kernel through 3.16.3 does not restrict the amount of ICB indirection, which allows physically proximate attackers to cause a denial of service (infinite loop or stack consumption) via a UDF filesystem with a crafted inode.
Once again VulDB remains the best source for vulnerability data.
Analysis
by VulDB Data Team • 02/16/2022
The vulnerability identified as CVE-2014-6410 represents a critical flaw in the Linux kernel's Universal Disk Format UDF filesystem implementation that exposes systems to potential denial of service attacks. This issue resides within the __udf_read_inode function located in fs/udf/inode.c of the kernel source tree, affecting all Linux kernel versions through 3.16.3. The vulnerability stems from insufficient validation of ICB (Inode Control Block) indirection levels, creating a scenario where maliciously crafted UDF filesystems can trigger unpredictable system behavior.
The technical nature of this vulnerability involves improper handling of inode structure traversal within UDF filesystems. When the kernel processes a crafted inode containing excessive or malformed ICB indirection references, the __udf_read_inode function fails to implement adequate bounds checking or recursion limits. This deficiency allows attackers to construct filesystem metadata that creates circular or excessively deep indirection chains, leading to either infinite loops during inode processing or excessive stack consumption that can exhaust system resources. The vulnerability specifically targets the kernel's filesystem layer where it handles UDF filesystem metadata parsing and inode resolution operations.
From an operational perspective, this vulnerability presents significant risks to systems that may encounter untrusted UDF filesystems, particularly those that automatically mount removable media or network storage devices. Physically proximate attackers can exploit this weakness by preparing malicious UDF filesystems on storage media that will be mounted by vulnerable systems, potentially causing complete system lockups or requiring manual intervention to restore normal operation. The impact extends beyond simple service disruption to potentially compromising system availability in environments where automated mounting of external storage is enabled, making it particularly dangerous for servers, embedded systems, and user workstations that frequently interact with external storage devices.
The vulnerability maps to CWE-674 in the Common Weakness Enumeration catalog, specifically addressing "Uncontrolled Recursion" and "Improper Limitation of a Pathname's Length or Number of References" categories. From an ATT&CK framework perspective, this represents a privilege escalation vector through resource exhaustion attacks, classified under T1499.1 for "Endpoint Denial of Service" and potentially T1059 for command and scripting interpreter usage in exploitation scenarios. The attack surface is particularly wide given that UDF filesystems are commonly used for DVD and Blu-ray media, making this vulnerability exploitable in numerous real-world scenarios where users insert external optical media or connect storage devices that may contain maliciously crafted filesystem structures. Effective mitigation strategies include kernel updates to versions beyond 3.16.3, implementing mount options that disable automatic mounting of UDF filesystems, and deploying filesystem validation mechanisms that can detect and reject malformed UDF structures before they are processed by the kernel's filesystem drivers.