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.
CVE-2003-0955
- No confirmed exploitation signals yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- —
- EG Score
- 0.0(none)
- EPSS
- 63.0%
- KEV
- Not listed
Published
December 15, 2003
Last Modified
June 16, 2026
References (14)
- cve@mitreftp://ftp.openbsd.org/pub/OpenBSD/patches/3.4/common/005_exec.patch
- cve@mitrehttp://lists.grok.org.uk/pipermail/full-disclosure/2003-November/013315.html
- cve@mitrehttp://marc.info/?l=openbsd-security-announce&m=106808820119679&w=2
- cve@mitrehttp://marc.info/?l=openbsd-security-announce&m=106917441524978&w=2
- cve@mitrehttp://www.guninski.com/msuxobsd2.html
- cve@mitrehttp://www.openbsd.org/errata33.html
- cve@mitrehttp://www.securityfocus.com/bid/8978
- af854a3a-2127-422b-91ae-364da2661108ftp://ftp.openbsd.org/pub/OpenBSD/patches/3.4/common/005_exec.patch
- af854a3a-2127-422b-91ae-364da2661108http://lists.grok.org.uk/pipermail/full-disclosure/2003-November/013315.html
- af854a3a-2127-422b-91ae-364da2661108http://marc.info/?l=openbsd-security-announce&m=106808820119679&w=2
- af854a3a-2127-422b-91ae-364da2661108http://marc.info/?l=openbsd-security-announce&m=106917441524978&w=2
- af854a3a-2127-422b-91ae-364da2661108http://www.guninski.com/msuxobsd2.html
- af854a3a-2127-422b-91ae-364da2661108http://www.openbsd.org/errata33.html
- af854a3a-2127-422b-91ae-364da2661108http://www.securityfocus.com/bid/8978
Data Freshness Timeline
(refreshed 3× in last 7d / 23× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-11 08:22 UTCEPSS rescore
- 2026-07-11 08:22 UTCEPSS rescore
- 2026-07-08 15:09 UTCEPSS rescore
- 2026-07-06 02:19 UTCEPSS rescore
- 2026-07-04 06:26 UTCEPSS rescore
- 2026-07-02 14:00 UTCEPSS rescore
- 2026-06-28 04:52 UTCEPSS rescore
- 2026-06-27 03:04 UTCEPSS rescore
- 2026-06-23 21:29 UTCEPSS rescore
- 2026-06-22 14:22 UTCEPSS rescore
- 2026-06-21 14:52 UTCEPSS rescore
- 2026-06-21 01:56 UTCEPSS rescore
- 2026-06-19 19:22 UTCEPSS rescore
- 2026-06-19 19:22 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-18 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-17 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-16 17:49 UTCEPSS rescore
- 2026-06-15 17:43 UTCEPSS rescore
- 2026-06-14 23:13 UTCEPSS rescore
- 2026-06-14 23:13 UTCEPSS rescore
- 2026-06-13 22:56 UTCEPSS rescore
- 2026-06-12 23:08 UTCEPSS rescore
Show 37 moreShow fewer
- 2026-06-11 13:55 UTCEPSS rescore
- 2026-06-10 22:13 UTCEPSS rescore
- 2026-06-10 13:17 UTCEPSS rescore
- 2026-06-08 14:13 UTCEPSS rescore
- 2026-06-07 15:21 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-06 13:44 UTCEPSS rescore
- 2026-06-05 22:43 UTCEPSS rescore
- 2026-06-05 22:43 UTCEPSS rescore
- 2026-06-05 06:07 UTCEPSS rescore
- 2026-06-04 13:09 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 17:03 UTCEG score recompute
- 2026-05-31 17:03 UTCGHSA enrichment
- 2026-05-31 00:13 UTCEPSS rescore
- 2026-05-31 00:13 UTCEPSS rescore
- 2026-05-29 13:40 UTCEPSS rescore
- 2026-05-29 13:40 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-27 13:37 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 13:41 UTCEPSS rescore
- 2026-05-26 07:16 UTCEPSS rescore
- 2026-05-26 07:16 UTCEPSS rescore
- 2026-05-24 16:42 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-20 22:36 UTCEPSS rescore
- 2026-05-20 11:20 UTCEPSS rescore
- 2026-05-20 11:20 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
- 2026-05-18 21:29 UTCEPSS rescore
Publicly available exploits
(2 references)Working exploit code is in the public domain (2 Exploit-DB entries). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Exploit-DBEDB-125✓ verifiedFirst seen Nov 19, 2003
OpenBSD 2.x < 3.3 - 'exec_ibcs2_coff_prep_zmagic()' kernel stack overflow
Open source ↗ - Exploit-DBEDB-118✓ verifiedFirst seen Nov 7, 2003
OpenBSD - 'ibcs2_exec' Kernel Code Execution
Open source ↗
Frequently asked(4)
What is CVE-2003-0955?
When was CVE-2003-0955 disclosed?
Is CVE-2003-0955 actively exploited?
How do I remediate CVE-2003-0955?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2003-0955
Is Your Infrastructure Affected by CVE-2003-0955?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.