The kernel in Red Hat Enterprise Linux 3, when running on SMP systems, allows local users to cause a denial of service (deadlock) by runnin…

published 2006-10-17 20 y ago modified 2026-06-16 4 mo ago also EUVD-2006-4330

cvss: 5.5; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 0.4%; EPSS 0.4% chance of exploitation in 30 days, percentile 33%
public exploits: 0; none known

The kernel in Red Hat Enterprise Linux 3, when running on SMP systems, allows local users to cause a denial of service (deadlock) by running the shmat function on an shm at the same time that shmctl is removing that shm (IPC_RMID), which prevents a spinlock from being unlocked.

Patch / fix

distros 1

kernel RHEL 3 2.4.21-47.0.1.EL
kernel-smp RHEL 3 2.4.21-47.0.1.EL
kernel-BOOT RHEL 3 2.4.21-47.0.1.EL
kernel-source RHEL 3 2.4.21-47.0.1.EL
kernel-hugemem RHEL 3 2.4.21-47.0.1.EL
kernel-unsupported RHEL 3 2.4.21-47.0.1.EL
kernel-smp-unsupported RHEL 3 2.4.21-47.0.1.EL
kernel-hugemem-unsupported RHEL 3 2.4.21-47.0.1.EL

red hat advisories RHSA-2006:0710

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2006-4342 updated 2025-11-21

security flaw

Red Hat Desktop version 3 kernel 2.4.21-47.0.1.EL, kernel-smp 2.4.21-47.0.1.EL, kernel-BOOT 2.4.21-47.0.1.EL, kernel-source 2.4.21-47.0.1.EL, kernel-hugemem 2.4.21-47.0.1.EL, kernel-unsupported 2.4.21-47.0.1.EL, +2 more Red Hat Enterprise Linux AS version 3 kernel 2.4.21-47.0.1.EL, kernel-smp 2.4.21-47.0.1.EL, kernel-BOOT 2.4.21-47.0.1.EL, kernel-source 2.4.21-47.0.1.EL, kernel-hugemem 2.4.21-47.0.1.EL, kernel-unsupported 2.4.21-47.0.1.EL, +2 more Red Hat Enterprise Linux ES version 3 kernel 2.4.21-47.0.1.EL, kernel-smp 2.4.21-47.0.1.EL, kernel-BOOT 2.4.21-47.0.1.EL, kernel-source 2.4.21-47.0.1.EL, kernel-hugemem 2.4.21-47.0.1.EL, kernel-unsupported 2.4.21-47.0.1.EL, +2 more Red Hat Enterprise Linux WS version 3 kernel 2.4.21-47.0.1.EL, kernel-smp 2.4.21-47.0.1.EL, kernel-BOOT 2.4.21-47.0.1.EL, kernel-source 2.4.21-47.0.1.EL, kernel-hugemem 2.4.21-47.0.1.EL, kernel-unsupported 2.4.21-47.0.1.EL, +2 more
fixed: vendor fix RHSA-2006:0710

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.39% chance of exploitation in the next 30 days, higher than 33% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

bugzilla.redhat.com https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=205618 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	4.0	AV:L/AC:H/Au:N/C:N/I:N/A:C

Classification

Weakness

CWE-667 Improper Locking

References

bugzilla.redhat.com /bugzilla/show_bug.cgi?id=205618
exploit, issue-tracking
redhat.com /support/errata/RHSA-2006-0710.html
vendor-advisory, broken-link
kb.cert.org /vuls/id/245984
third-party-advisory, us-government-resource
oval.cisecurity.org /repository/search/definition/oval%3Aorg.mitre.oval%3Adef%3A9649
vdb-entry, signature, broken-link
secunia.com /advisories/23064
third-party-advisory, broken-link
support.avaya.com /elmodocs2/security/ASA-2006-254.htm
third-party-advisory
secunia.com /advisories/22497
third-party-advisory, broken-link

Sources

CVE List CVE-2006-4342
NVD CVE-2006-4342

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.

Summary