Linux VserverApplication

CVE-2006-4243

CRITICAL · 9.8 CVSS v3.1 Published 2019-11-06
Fix available
A fix is available. Upgrade to 2.6.17 or later.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
linux vserver 2.6 before 2.6.17 suffers from privilege escalation in remount code.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Linux VServer 2.6 versions before 2.6.17 contain a privilege escalation vulnerability in the remount code that allows local users to gain elevated privileges through improper permission checking during filesystem remount operations.

MitigationUpgrade Linux VServer to version 2.6.17 or later to address the remount code privilege escalation, or apply the specific security patch if upgrading is not feasible.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux VserverApplication
Affected:>= 1.9.0, < 2.6.17

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Confirm Linux VServer is installed
    Run 'which vserver' or check for VServer processes with 'ps aux | grep vserver'
    Affected if The vserver command exists or VServer-related processes are running
  2. Identify VServer version
    Run 'vserver --version' to get the VServer utility version, or 'uname -r' to check if the kernel is VServer-enabled (often contains 'vserver' in the version string)
    Affected if The version returned is >= 1.9.0 and < 2.6.17
  3. Verify remount capability is accessible
    Check if non-privileged users can invoke mount operations within a VServer context. This typically involves examining /proc/mounts or using 'vserver <name> exec mount -o remount ...'
    Affected if Remount operations can be executed by local users without proper privilege escalation controls
  4. Compare against affected version range
    Document the exact VServer version identified and compare it to the vulnerable range: 1.9.0 through versions before 2.6.17
    Affected if The installed version falls within >= 1.9.0 and < 2.6.17

A system is affected if Linux VServer version 1.9.0 or higher but lower than 2.6.17 is installed and local users can perform filesystem remount operations within the VServer environment.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 2.6.17 or later
Fixed in 2.6.17
Interim mitigation

Upgrade Linux VServer to version 2.6.17 or later to address the remount code privilege escalation, or apply the specific security patch if upgrading is not feasible.

Recommended fix Moderate confidence

Linux Vserver 2.6.17 or later

  1. 1. Identify the currently installed Linux Vserver version using 'vserver --version' or checking package management
  2. 2. Ensure all running vserver instances are properly shut down before upgrading
  3. 3. Update the package repository and upgrade to Linux Vserver 2.6.17 or later using the system's package manager (e.g., apt-get update && apt-get install linux-vserver or equivalent)
  4. 4. After upgrading, reboot the host system to load the new kernel/vserver components
  5. 5. Verify the new version is installed and the remount functionality is properly secured
  6. 6. Test that vserver instances can be started and function correctly with the updated version
Caveat Upgrading the kernel/vserver components may require host system reboot; ensure vserver workloads are properly stopped and data is backed up before proceeding

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Linux Vserver Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing12.0 h
  • Review / QA4.0 h
28.0 hours of engineering $4,760
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2006-4243 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2006-4243 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data