CVE-2026-57843 PUBLISHED

NetBSD mm_open() PK_KMEM Flag Kernel Pointer Information Disclosure

Assigner: VulnCheck
Reserved: 25.06.2026 Published: 11.09.2026 Updated: 11.09.2026

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.

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CVSS Score: 6.8

Product Status

Vendor The NetBSD Foundation
Product NetBSD
Versions Default: unaffected
  • affected from 9.0 to 9.5 (excl.)
  • affected from 10.0 to 10.1 (incl.)

Credits

  • Tristan CLERC finder
  • VulnCheck coordinator

References

Problem Types

  • Incorrect Permission Assignment for Critical Resource CWE