High severity · published Sep 11, 2026
CVE-2026-57842
NetBSD COMPAT_NETBSD32 Double Free / Use-After-Free via recvmsg() msg_iovlen
7.0
CVSS
0.1%
EPSS
No
On KEV
Description
NetBSD contains a use-after-free and double-free vulnerability in msg_recv_copyin() within the COMPAT_NETBSD32 compatibility layer due to a missing return statement before the cleanup label on the success path. Any local user able to execute a 32-bit binary on a 64-bit NetBSD system can trigger a kernel panic or memory corruption by calling recvmsg() with msg_iovlen between 9 and IOV_MAX, causing the kernel to access a freed iovec buffer and subsequently free the same allocation a second time.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
High
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 3% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NE
NetBSD · The NetBSD Foundation
8.0 through 8.3; 9.0 before 9.5; 10.0 through 10.1 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-57842
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-57842
vendor-advisory
https://gnats.netbsd.org/60373
third-party-advisory
https://www.vulncheck.com/advisories/netbsd-compat-netbsd32-double-free-use-after-free-via-recvmsg-msg-iovlen
More from NetBSD
7.0
CVE-2026-53996
NetBSD hdaudio(4) Driver Privilege Bypass Use-After-Free via HDAUDIO_FGRP_SETCONFIG ioctl
5.5
CVE-2026-57843
NetBSD mm_open() PK_KMEM Flag Kernel Pointer Information Disclosure
