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Vulnerability DatabaseCVE-2025-39943
CVE-2025-39943:
Linux Debian vulnerability analysis and mitigation
Overview
CVE-2025-39943 is a vulnerability discovered in the Linux kernel affecting the ksmbd SMBDirect implementation. The vulnerability was disclosed on October 4, 2025, and involves validation issues with dataoffset and datalength fields in the smbdirectdata_transfer struct (NVD).
Technical details
The vulnerability exists in the ksmbd SMBDirect implementation where the dataoffset and datalength fields of the smbdirectdatatransfer struct are not properly validated. This lack of validation could lead to out-of-bounds issues during the recvdone operation (NVD, Debian).
Impact
If exploited, this vulnerability could result in out-of-bounds memory access in the Linux kernel's SMBDirect implementation, potentially affecting system stability and security (NVD).
Mitigation and workarounds
Fixes have been implemented in various Linux distributions. Debian has released fixes in version 6.16.9-1 for unstable and 6.16.12-2 for sid. Ubuntu has marked several kernel versions as requiring updates (Debian, Ubuntu).
Additional resources
Source: This report was generated using AI
Related Linux Debian vulnerabilities:
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