dbcve.org
Big Ip Edge GatewayWeb browser · F5

CVE-2016-5023

HIGH · 7.5 CVSS v3.0 Published 2016-08-26
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
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
Virtual servers in F5 BIG-IP systems 11.2.1 HF11 through HF15, 11.4.1 HF4 through HF10, 11.5.3 through 11.5.4, 11.6.0 HF5 through HF7, and 12.0.0, when configured with a TCP profile, allow remote attackers to cause a denial of service (Traffic Management Microkernel restart) via crafted network traffic.

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

Virtual servers in F5 BIG-IP systems running specific hotfix versions (11.2.1 HF11-HF15, 11.4.1 HF4-HF10, 11.5.3-11.5.4, 11.6.0 HF5-HF7, and 12.0.0) configured with a TCP profile are vulnerable to remote denial-of-service attacks via crafted network traffic that triggers a Traffic Management Microkernel (TMM) restart.

MitigationApply the appropriate F5 hotfix or upgrade to a patched version as specified in the F5 security advisory for 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 Edge GatewayWeb browser
Affected:= 11.2.1
Big Ip Protocol Security ModulePlugin / extension
Affected:= 11.2.1= 11.4.1
Big Ip AnalyticsApplication
Affected:= 11.2.1= 11.4.1= 11.5.3= 11.5.4= 11.6.0= 12.0.0
Big Ip Application Security ManagerApplication
Affected:= 11.2.1= 11.4.1= 11.5.3= 11.5.4= 11.6.0= 12.0.0
Big Ip Advanced Firewall ManagerApplication
Affected:= 11.4.1= 11.5.3= 11.5.4= 11.6.0= 12.0.0
Big Ip Domain Name SystemApplication
Affected:= 12.0.0
Big Ip Policy Enforcement ManagerApplication
Affected:= 11.4.1= 11.5.3= 11.5.4= 11.6.0= 12.0.0
Big Ip Wan Optimization ManagerApplication
Affected:= 11.2.1

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
None
Integrity
None
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/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. Identify the installed BIG-IP product version
    Run the command 'tmsh show sys version' or check the GUI under System > Software > Image List to determine the exact version and hotfix level of the F5 BIG-IP system
    Affected if The version matches any of the affected ranges: 11.2.1 HF11-HF15, 11.4.1 HF4-HF10, 11.5.3, 11.5.4, 11.6.0 HF5-HF7, or 12.0.0
  2. Verify the BIG-IP product module
    Confirm which F5 module is running (Analytics, ASM, AFM, DNS, PEM, WAN Optimization, or Edge Gateway) by checking the licensed modules under System > License or via 'tmsh show sys license'
    Affected if The system is running any of the affected products: Big Ip Edge Gateway, Protocol Security Module, Analytics, Application Security Manager, Advanced Firewall Manager, Domain Name System, Policy Enforcement Manager, or Wan Optimization Manager
  3. Identify virtual servers with TCP profiles configured
    Review virtual server configurations via the GUI under Local Traffic > Virtual Servers or run 'tmsh list ltm virtual' to list all virtual servers and their associated TCP profiles
    Affected if Any virtual server is configured with a TCP profile (such as the default 'tcp' profile or a custom TCP profile)
  4. Confirm the hotfix level for affected base versions
    Check the detailed hotfix version by running 'tmsh show sys version' or examining the software image filename, as the vulnerability applies only to specific hotfix ranges within the base versions listed
    Affected if Running a hotfix within the vulnerable ranges (11.2.1 HF11-HF15, 11.4.1 HF4-HF10, or 11.6.0 HF5-HF7)

The system is affected if it runs any of the listed F5 BIG-IP product versions with a virtual server configured using a TCP profile.

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
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the appropriate F5 hotfix or upgrade to a patched version as specified in the F5 security advisory for this vulnerability.

Fix this in Big Ip Edge Gateway Scoped from the published advisory
  • Consultation3.0 h
  • Implementation4.0 h
  • Testing4.0 h
  • Review / QA2.0 h
13.0 hours of engineering $2,280
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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-2016-5023 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