Vulnerability in Linux Kernel Affects Shared skb Fragments

CVE-2026-43284

What is CVE-2026-43284?

CVE-2026-43284 is a vulnerability found in the Linux kernel, specifically impacting how shared socket buffers (skb) handle data during the encryption and decryption processes in network packets. The flaw arises from the manner in which the xfrm transport layer processes ESP (Encapsulating Security Payload) packets within UDP (User Datagram Protocol). When shared skb fragments are spliced from a pipe, they may be incorrectly marked, allowing for certain operations to modify packet data directly in-place without copying. This poses a risk as it could enable unauthorized decryption of sensitive information, essentially allowing attackers to manipulate data within the packet without proper ownership checks. The potential for exploiting this vulnerability could lead to data leakage and weaken the overall security of systems utilizing the Linux kernel.

Potential impact of CVE-2026-43284

1. Data Leakage: Due to the improper handling of shared skb fragments, there’s a risk of sensitive information being decrypted and accessed by unauthorized entities, leading to potential data breaches.

2. Integrity Compromise: Attackers could exploit this vulnerability to modify data in transit, potentially leading to compromised integrity of network communications, affecting the reliability of data transmission across systems.

3. Increased Attack Surface: The vulnerability expands the attack vectors against systems leveraging the Linux kernel for networking, which could be targeted by malicious actors to disrupt services or gain unauthorized access to resources.

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