CVE-2026-57843

NetBSD contains an information disclosure vulnerability in mm_open() within sys/dev/mm.c that allows unprivileged local users to obtain real kernel virtual addresses by opening world-accessible devices such as /dev/null or /dev/zero, which incorrectly receive the PK_KMEM process flag. Attackers can exploit this misconfigured flag to bypass the CANSEE_KPTR obfuscation mechanism and read kernel virtual addresses for sensitive kernel structures including struct proc, kauth_cred, filedesc, and vmspace via sysctl KERN_PROC queries.

  • Published Sep 11, 2026
  • CVSS 6.8 medium
  • 0.1% chance of exploitation in the next 30 days (EPSS)

Affected software

CVE-2026-57843 at the National Vulnerability Database