CVE-2014-0131 in Linux
Summary
by MITRE
Use-after-free vulnerability in the skb_segment function in net/core/skbuff.c in the Linux kernel through 3.13.6 allows attackers to obtain sensitive information from kernel memory by leveraging the absence of a certain orphaning operation.
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Analysis
by VulDB Data Team • 05/08/2026
The CVE-2014-0131 vulnerability represents a critical use-after-free flaw in the Linux kernel's networking subsystem that emerged in kernel versions through 3.13.6. This vulnerability resides within the skb_segment function located in net/core/skbuff.c, which is responsible for segmenting network packets during transmission. The flaw occurs when the kernel fails to properly orphan packet buffers during certain segmentation operations, creating a scenario where freed memory can be accessed by malicious actors. This particular vulnerability demonstrates the inherent complexity of kernel memory management and the dangerous consequences that can arise from improper resource handling in low-level system components.
The technical exploitation of this vulnerability stems from the absence of a crucial orphaning operation that should occur during packet segmentation. When network packets are processed through the skb_segment function, the kernel allocates and manages packet buffers in memory. However, under specific conditions involving packet fragmentation and reassembly, the function fails to properly orphan the buffer references, leading to a situation where freed memory structures remain accessible. Attackers can leverage this condition to read kernel memory contents, potentially extracting sensitive information such as cryptographic keys, user credentials, or other confidential data stored in kernel space. This use-after-free condition falls under the CWE-416 vulnerability category, which specifically addresses the use of freed memory, and represents a classic example of improper memory management in kernel code.
The operational impact of CVE-2014-0131 extends beyond simple information disclosure, as it provides attackers with the capability to gain unauthorized access to kernel memory spaces that should remain protected. The vulnerability can be exploited remotely through network-based attacks, making it particularly dangerous in environments where systems are exposed to untrusted network traffic. When an attacker successfully exploits this vulnerability, they can potentially extract sensitive kernel data that could be used for further exploitation attempts, including privilege escalation or system compromise. The attack vector typically involves sending specially crafted network packets that trigger the vulnerable code path, causing the kernel to perform the problematic segmentation operation that leads to memory access after deallocation.
Mitigation strategies for CVE-2014-0131 primarily focus on updating to patched kernel versions where the orphaning operation has been properly implemented in the skb_segment function. System administrators should prioritize applying kernel updates from their respective distributions, as the vulnerability was addressed in kernel versions beyond 3.13.6. Additionally, network segmentation and firewall rules can help reduce the attack surface by limiting exposure to potentially malicious network traffic. The vulnerability's classification under ATT&CK technique T1068, which covers exploit for privilege escalation, underscores the importance of maintaining up-to-date systems and implementing proper network monitoring to detect anomalous traffic patterns that might indicate exploitation attempts. Organizations should also consider implementing kernel memory protection mechanisms and regularly auditing their kernel configurations to ensure they are not running vulnerable versions that could be exploited by adversaries seeking to leverage this use-after-free condition.