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CVE-2025-40072 is a NULL pointer dereference in the Linux kernel fanotify subsystem. In do_fanotify_mark(), the return value of mnt_ns_from_dentry() was dereferenced through mntns->user_ns without first confirming it was non-NULL. A supplied path that is not a mount-namespace object can cause the helper to return NULL and trigger the fault. The issue was introduced in Linux kernel 6.16 and affects fanotify mount-namespace monitoring.
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A Linux kernel fanotify flaw causing a kernel NULL pointer dereference in do_fanotify_mark() when mnt_ns_from_dentry() returns NULL and the result is dereferenced without validation.
A NULL pointer dereference vulnerability in the Linux kernel fanotify subsystem, triggered when namespace-monitoring flags are used with an object that is not a mount namespace, allowing unprivileged users to affect system operation.
A Linux kernel fanotify NULL pointer dereference caused by failing to validate the return value of mnt_ns_from_dentry() before dereferencing it, allowing unprivileged users to disrupt the system.
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Cross-references every affected SKU, including bundled OEM variants.
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