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.

CVSS v3 5.5 MEDIUM

5.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://gnats.netbsd.org/60373
https://www.vulncheck.com/advisories/netbsd-mm-open-pk-kmem-flag-kernel-pointer-information-disclosure

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-11 14:17

Updated : 2026-09-11 14:17

NVD link : CVE-2026-57843

Mitre link : CVE-2026-57843

CVE.ORG link : CVE-2026-57843

JSON object : View

Products Affected

No product.

CWE

CWE-732

Incorrect Permission Assignment for Critical Resource

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