Read the docs
TI-2026-41654 Aliases CVE-2026-57843GHSA-p59p-jjhh-5885

NetBSD mm_open() PK_KMEM Flag Kernel Pointer Information Disclosure

Priority LOW 29CWE-732Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00145 3rd percentileScored 2026-11-07
Fix Fixed NetBSD (The NetBSD Foundation): 9.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
The NetBSD FoundationNetBSD9.0 to before 9.5; 10.0 – 10.19.5Patch availableCNA
  • NetBSD VendorThe NetBSD Foundation Affected 9.0 to before 9.5; 10.0 – 10.1 Fixed in 9.5 Patch available CNA

Remediation

  • Fix · CNA NetBSD (The NetBSD Foundation) Fixed in 9.5

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    The NetBSD Foundation NetBSD — Patch Commit

    2 records Highest priority Priority LOW 2 LOW

    Other records, highest priority first

    • TI-2026-41653 NetBSD COMPAT_NETBSD32 Double Free / Use-After-Free via recvmsg() msg_iovlenPriority LOW 33
    Show all 2 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-57843
  2. 2026-10-03 Alias added: GHSA-p59p-jjhh-5885

References

Patch 1

  • TI-2026-41653 NetBSD COMPAT_NETBSD32 Double Free / Use-After-Free via recvmsg() msg_iovlen CVSS 4.0HIGH 7.3
  • TI-2026-38948 NetBSD hdaudio(4) Driver Privilege Bypass Use-After-Free via HDAUDIO_FGRP_SETCONFIG ioctl CVSS 4.0HIGH 7.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences