CVE-2025-37947

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 6.6.93 Linux kernel versions prior to 6.1.140-1 (Debian 11 bullseye) Linux kernel versions prior to 6.1.140-1~deb11u1 (Debian 11 bullseye)

Description The Linux kernel contains a flaw in the ksmbd module related to out-of-bounds stream writes. Specifically, the ksmbd vfs stream write() function did not validate whether the write offset (*pos) was within the bounds of the existing stream data length (v len). If *pos was greater than or equal to v len, this could lead to an out-of-bounds memory write. A patch has been implemented to add a check to ensure *pos is less than v len before proceeding, returning -EINVAL if the condition fails. Exploitation of this vulnerability can lead to local privilege escalation. Proof-of-concept (PoC) exploits are publicly available.

Recommendations Upgrade to Linux kernel version 6.6.93 or later. Upgrade to Linux kernel version 6.1.140-1 or later for Debian 11 bullseye. Upgrade to Linux kernel version 6.1.140-1~deb11u1 or later for Debian 11 bullseye.