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Vulnerability DatabaseCVE-2025-39720
CVE-2025-39720:
CBL Mariner vulnerability analysis and mitigation
Overview
In the Linux kernel, a vulnerability (CVE-2025-39720) was discovered related to the ksmbd component. The issue was identified and disclosed on September 5, 2025, affecting the Linux kernel's implementation of the SMB server. The vulnerability involves a refcount leak in the ksmbd component that occurs when ksmbd_conn_releasing(opinfo->conn) returns true (NVD).
Technical details
The vulnerability stems from a refcount leak where the refcount is not decremented properly when ksmbd_conn_releasing(opinfo->conn) returns true. This improper handling prevents the count from reaching zero, consequently preventing the memory from being released. The vulnerability has been assigned a CVSS v3.1 base score of 5.5, indicating moderate severity (Rapid7).
Impact
The primary impact of this vulnerability is a resource leak in the system. When exploited, it prevents proper memory release, which could lead to resource exhaustion over time. This could potentially affect system stability and performance (NVD).
Additional resources
Linux Distribution fix status
Fix availability across major Linux distributions and their releases.
bionic
linux
bionic (esm-infra)
linux
bionic (fips-updates)
linux-fips
bionic (fips)
linux-fips
devel
linux
focal
linux
focal (esm-infra)
linux-hwe-5.15
focal (fips-updates)
linux-fips
Source: This report was generated using AI
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