Medium severity · published Sep 11, 2026
CVE-2026-57843
NetBSD mm_open() PK_KMEM Flag Kernel Pointer Information Disclosure
5.5
CVSS
0.1%
EPSS
No
On KEV
Description
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 vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 4% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
NetBSD · The NetBSD Foundation
9.0 before 9.5; 10.0 through 10.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-57843
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-57843
vendor-advisory
https://gnats.netbsd.org/60373
third-party-advisory
https://www.vulncheck.com/advisories/netbsd-mm-open-pk-kmem-flag-kernel-pointer-information-disclosure
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