CVE-2003-1366

OpenBSD 2.0-3.2 - Unauthorized File Read via chpass Hard Link Attack

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2003-1366. PoCs published by Marc Bevand.

AI-analyzed exploit summary This exploit leverages a race condition in OpenBSD's chpass utility to read arbitrary files by manipulating the temporary file used during password changes. The attacker creates a symlink to a target file, tricking chpass into displaying its contents.

Description

chpass in OpenBSD 2.0 through 3.2 allows local users to read portions of arbitrary files via a hard link attack on a temporary file used to store user database information.

Exploits (1)

exploitdb WORKING POC VERIFIED
by Marc Bevand · textlocalopenbsd
https://www.exploit-db.com/exploits/22210

This exploit leverages a race condition in OpenBSD's chpass utility to read arbitrary files by manipulating the temporary file used during password changes. The attacker creates a symlink to a target file, tricking chpass into displaying its contents.

Classification
Working Poc 90%
Attack Type
Info Leak
Complexity
Moderate
Reliability
Racy
Target: OpenBSD chpass (and chfn, chsh)
Auth required
Prerequisites: local access · ability to suspend and resume processes
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (6)

Core 6
Core References
Third Party Advisory, VDB Entry vdb-entry x_refsource_bid
http://www.securityfocus.com/bid/6748
Various Sources x_refsource_misc
http://www.epita.fr/~bevand_m/asa/asa-0001
Third Party Advisory, VDB Entry vdb-entry x_refsource_sectrack
http://www.securitytracker.com/id?1006035
Third Party Advisory, VDB Entry mailing-list x_refsource_bugtraq
http://www.securityfocus.com/archive/1/309962
Third Party Advisory, VDB Entry vdb-entry x_refsource_xf
https://exchange.xforce.ibmcloud.com/vulnerabilities/11233
Third Party Advisory third-party-advisory x_refsource_sreason
http://securityreason.com/securityalert/3238

Scores

EPSS 0.0050
EPSS Percentile 38.8%

Details

CWE
CWE-200
Status published
Products (13)
openbsd/openbsd 2.0
openbsd/openbsd 2.1
openbsd/openbsd 2.2
openbsd/openbsd 2.3
openbsd/openbsd 2.4
openbsd/openbsd 2.5
openbsd/openbsd 2.6
openbsd/openbsd 2.7
openbsd/openbsd 2.8
openbsd/openbsd 2.9
... and 3 more
Published Dec 31, 2003
Tracked Since Feb 18, 2026