Information Disclosure Vulnerability in NetBSD's mm_open() Function

CVE-2026-57843

What is CVE-2026-57843?

NetBSD suffers from an information disclosure vulnerability in the mm_open() function located in sys/dev/mm.c. This vulnerability allows unprivileged local users to access real kernel virtual addresses by interacting with world-accessible devices such as /dev/null or /dev/zero. A misconfigured PK_KMEM process flag grants attackers the ability to bypass the CANSEE_KPTR obfuscation mechanism, enabling unauthorized readings of sensitive kernel structures. Exploitation can lead to exposure of critical information through sysctl KERN_PROC queries, potentially compromising the integrity and confidentiality of the system.

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