Openbsd ≫ Openbsd

sys/kern/sysv_sem.c in OpenBSD through 7.9 has a use-after-free allowing local privilege escalation to root. This is a context switch use-after-free after tsleep in sys_semget().

OpenBSD before commit 6a23123 (2026-06-18) contains an out-of-bounds read vulnerability in the mpls_do_error function within sys/netmpls/mpls_input.c that allows remote attackers to disclose kernel stack memory by sending crafted MPLS frames with 16 ...

sppp_pap_input in sys/net/if_spppsubr.c in OpenBSD before 076e2b1 allows authentication bypass via certain zero values for lengths.

In OpenBSD through 7.8, the slaacd and rad daemons have an infinite loop when they receive a crafted ICMPv6 Neighbor Discovery (ND) option (over a local network) with length zero, because of an "nd_opt_len * 8 - 2" expression with no preceding check ...

openrsync through 0.5.0, as used in OpenBSD through 7.8 and on other platforms, allows a client to cause a server SIGSEGV by specifying a length of zero for block data, because the relationship between p->rem and p->len is not checked.

In OpenBSD 7.6 before errata 006 and OpenBSD 7.5 before errata 015, traffic sent over wg(4) could result in kernel crash.

In OpenBSD 7.4 before errata 014, vmm(4) did not restore GDTR limits properly on Intel (VMX) CPUs.

In OpenBSD 7.5 before errata 009 and OpenBSD 7.4 before errata 022, exclude any '/' in readdir name validation to avoid unexpected directory traversal on untrusted file systems.

In OpenBSD 7.4 before errata 006 and OpenBSD 7.3 before errata 020, httpd(8) is vulnerable to a NULL dereference when handling a malformed fastcgi request.

In OpenBSD 7.5 before errata 008 and OpenBSD 7.4 before errata 021, avoid possible mbuf double free in NFS client and server implementation, do not use uninitialized variable in error handling of NFS server.