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Big Ip Local Traffic ManagerApplication · F5

CVE-2018-5518

MEDIUM · 5.4 CVSS v3.0 Published 2018-05-02
Fix available
A fix is available. Upgrade to after 13.1.0 or later.
See remediation →
56/100
Remediation priority · Elevated
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
On F5 BIG-IP 13.0.0-13.1.0.5 or 12.0.0-12.1.3.3, malicious root users with access to a VCMP guest can cause a disruption of service on adjacent VCMP guests running on the same host. Exploiting this vulnerability causes the vCMPd process on the adjacent VCMP guest to restart and produce a core file. This issue is only exploitable on a VCMP guest which is operating in "host-only" or "bridged" mode. VCMP guests which are "isolated" are not impacted by this issue and do not provide mechanism to exploit the vulnerability. Guests which are deployed in "Appliance Mode" may be impacted however the exploit is not possible from an Appliance Mode guest. To exploit this vulnerability root access on a guest system deployed as "host-only" or "bridged" mode is required.

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 · high confidence

A malicious root user with access to a VCMP guest running in 'host-only' or 'bridged' mode can cause the vCMPd process on adjacent VCMP guests running on the same host to restart, producing a core file and resulting in denial of service. Guests in 'isolated' mode are not vulnerable. This is a local privilege escalation attack within the VCMP hypervisor environment.

MitigationUpgrade F5 BIG-IP to a version beyond 13.1.0.5/12.1.3.3, or deploy affected guests in 'isolated' mode which is not impacted by this vulnerability.

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
Big Ip Local Traffic ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Application Acceleration ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Advanced Firewall ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip AnalyticsApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Access Policy ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Application Security ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Edge GatewayWeb browser
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0
Big Ip Global Traffic ManagerApplication
Affected:>= 12.0.0, <= 12.1.3>= 13.0.0, <= 13.1.0

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
Adjacent
Complexity
High
Privileges
High
User interaction
None
Scope
Changed
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.0/AV:A/AC:H/PR:H/UI:N/S:C/C:N/I:N/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. Check installed Big IP version
    Run 'tmsh show sys version' or 'bigpipe version' to display the installed software version
    Affected if Version falls within 12.0.0-12.1.3 or 13.0.0-13.1.0
  2. Verify VCMP is enabled
    Run 'tmsh show vcmp status' to determine if the Virtual Clustered Multiprocessing (VCMP) hypervisor is configured on the system
    Affected if VCMP is enabled and running
  3. Identify VCMP guest configuration mode
    Run 'tmsh list vcmp guest' to list all VCMP guests and their assigned VLAN mode (host-only, bridged, or isolated)
    Affected if Any guest is configured in 'host-only' or 'bridged' mode (not 'isolated' mode)
  4. Check for vCMPd crash core files
    Inspect /var/core/ directory for core files named 'vcmpd*' using 'ls -la /var/core/ | grep vcmpd'
    Affected if Recent vcmpd core files exist indicating process restart
  5. Review vCMPd process logs
    Run 'tmsh show logs vcmp' or check /var/log/vcmp.log for vCMPd process restart events and crashes
    Affected if Logs show unexpected vCMPd process restarts on multiple guests

System is affected if running a vulnerable Big IP version (12.0.0-12.1.3 or 13.0.0-13.1.0), VCMP is enabled, and any guest operates in 'host-only' or 'bridged' mode rather than 'isolated' mode.

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.

From vendor data
Upgrade available Upgrade to a release after 13.1.0
Interim mitigation

Upgrade F5 BIG-IP to a version beyond 13.1.0.5/12.1.3.3, or deploy affected guests in 'isolated' mode which is not impacted by this vulnerability.

Fix this in Big Ip Local Traffic Manager Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA4.0 h
40.0 hours of engineering $7,000
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $11,200.

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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-2018-5518 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