OpenBSD kernel 3.3 and 3.4 allows local users to cause a denial of service (kernel panic) and possibly execute arbitrary code in 3.4 via a program with an invalid header that is not properly handled by (1) ibcs2_exec.c in the iBCS2 emulation (compat_ibcs2) or (2) exec_elf.c, which leads to a stack-based buffer overflow.

BID:8978 | URL:http://www.securityfocus.com/bid/8978 | CONFIRM:http://marc.info/?l=openbsd-security-announce&m=106808820119679&w=2 | CONFIRM:http://marc.info/?l=openbsd-security-announce&m=106917441524978&w=2 | FULLDISC:20031104 OpenBSD kernel overflow, yet still *BSD much better than windows | URL:http://lists.grok.org.uk/pipermail/full-disclosure/2003-November/013315.html | MISC:http://www.guninski.com/msuxobsd2.html | OPENBSD:20031104 010: RELIABILITY FIX: November 4, 2003 | URL:http://www.openbsd.org/errata33.html | OPENBSD:20031105 005: RELIABILITY FIX: November 4, 2003 | URL:ftp://ftp.openbsd.org/pub/OpenBSD/patches/3.4/common/005_exec.patch