Linux Kernel Vulnerability in XFRM SPI Management

CVE-2025-39965

What is CVE-2025-39965?

CVE-2025-39965 is a vulnerability identified in the Linux kernel, specifically related to the management of Security Parameter Indexes (SPI) within the XFRM subsystem. The XFRM subsystem is responsible for handling IPsec transformations, which are crucial for securing IP communications through encryption. This vulnerability arises from improper handling of SPI values, where a state with an SPI value of zero is incorrectly created and managed within a list of active SPIs. This mismanagement leads to a use-after-free (UAF) condition, which can be exploited by attackers under specific circumstances. If exploited, this vulnerability could allow unauthorized access or control over systems running affected versions of the Linux kernel, potentially leading to serious security breaches.

Potential impact of CVE-2025-39965

1. Unauthorized Access: Exploiting this vulnerability can permit attackers to access sensitive data or unauthorized system functions. This could lead to data breaches or compromised credentials, impacting the confidentiality and integrity of organizational information.

2. Denial of Service: The exploitation of the UAF condition may result in system instability or crashes, leading to potential denial of service (DoS). Such disruptions can affect business operations, resulting in downtime and financial losses.

3. Further Exploitation Opportunities: Once an attacker gains a foothold through this vulnerability, they may leverage it as a stepping stone to deploy additional harmful activities, such as installing malware, establishing persistent access, or escalating privileges within the system. This could lead to more extensive system compromises and network infiltration.

References