CVE-2019-5603

HIGH

FreeBSD mqueuefs Improper Resource Shutdown or Release

Title source: llm
STIX 2.1

Exploitation Summary

EIP tracks 1 public exploit for CVE-2019-5603. PoCs published by raymontag.

AI-analyzed exploit summary This is a privilege escalation exploit for FreeBSD's mqueuefs vulnerabilities (CVE-2019-5603). It leverages a use-after-free (UaF) condition to manipulate file descriptors and escalate privileges by targeting /etc/libmap.conf.

Description

In FreeBSD 12.0-STABLE before r350261, 12.0-RELEASE before 12.0-RELEASE-p8, 11.3-STABLE before r350263, 11.3-RELEASE before 11.3-RELEASE-p1, and 11.2-RELEASE before 11.2-RELEASE-p12, system calls operating on file descriptors as part of mqueuefs did not properly release the reference allowing a malicious user to overflow the counter allowing access to files, directories, and sockets opened by processes owned by other users.

Exploits (1)

nomisec WORKING POC 1 stars
by raymontag · poc
https://github.com/raymontag/CVE-2019-5603

This is a privilege escalation exploit for FreeBSD's mqueuefs vulnerabilities (CVE-2019-5603). It leverages a use-after-free (UaF) condition to manipulate file descriptors and escalate privileges by targeting /etc/libmap.conf.

Classification
Working Poc 95%
Attack Type
Lpe
Complexity
Complex
Reliability
Racy
Target: FreeBSD (mqueuefs)
No auth needed
Prerequisites: FreeBSD system with vulnerable mqueuefs · Ability to execute code on the target system · Presence of /etc/libmap.conf
devstral-2 · analyzed Feb 16, 2026 Full analysis →

References (6)

Core 6
Core References
Vendor Advisory vendor-advisory x_refsource_freebsd
https://security.FreeBSD.org/advisories/FreeBSD-SA-19:15.mqueuefs.asc
Third Party Advisory x_refsource_confirm
https://security.netapp.com/advisory/ntap-20190814-0003/
Third Party Advisory vendor-advisory x_refsource_freebsd
https://security.FreeBSD.org/advisories/FreeBSD-SA-19:24.mqueuefs.asc
Broken Link mailing-list x_refsource_bugtraq
https://seclists.org/bugtraq/2019/Aug/35

Scores

CVSS v3 7.8
EPSS 0.0062
EPSS Percentile 45.1%
Attack Vector LOCAL
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Details

CWE
CWE-404
Status published
Products (4)
freebsd/freebsd 11.0
freebsd/freebsd 11.2 (12 CPE variants)
freebsd/freebsd 11.3
freebsd/freebsd 12.0 (8 CPE variants)
Published Jul 26, 2019
Tracked Since Feb 18, 2026