CVE-2026-57842: The Netbsd Foundation Netbsd

High severity, CVSS 7.0. EPSS: 0.1% chance of exploitation in the next 30 days.

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.

Affected products

• The Netbsd Foundation Netbsd: from 8.0, up to and including 8.3; from 9.0, before 9.5 (fixed in 9.5); from 10.0, up to and including 10.1

Published 2026-09-11. Last modified 2026-09-24.