Skip to content
Fencer Vulns
medium 5.5

CVE-2001-1559 json

The uipc system calls (uipc_syscalls.c) in OpenBSD 2.9 and 3.0 provide user mode return instead of versus rval kernel mode values to the fd…

published 2001-12-31 24 y ago modified 2026-06-16 4 mo ago also EUVD-2001-1536

cvss
5.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
1.5%
EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits
1
Exploit-DB

Summary

The uipc system calls (uipc_syscalls.c) in OpenBSD 2.9 and 3.0 provide user mode return instead of versus rval kernel mode values to the fdrelease function, which allows local users to cause a denial of service and trigger a null dereference.

Timeline

  1. First public exploit (EDB-21167)
  2. Published

Exploit prediction

1.48% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • EDB-21167 OpenBSD 2.x/3.0 - User Mode Return Value Denial of Service dos, 2001-12-03
  • archives.neohapsis.com http://archives.neohapsis.com/archives/bugtraq/2001-12/0014.html referenced PoC, tagged "exploit" by a source, unverified
  • monkey.org http://monkey.org/openbsd/archive/tech/0112/msg00015.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 5.5 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 2.1 AV:L/AC:L/Au:N/C:N/I:N/A:P

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.