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Big Ip Application Security ManagerApplication · F5

CVE-2026-40060

HIGH · 7.5 CVSS v3.1 Published 2026-05-13
Fix available
A fix is available. Upgrade to after 17.5.1 or later.
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
When a BIG-IP Advanced WAF or ASM security policy is configured on a virtual server, undisclosed requests can cause the bd process to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

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

This is a denial-of-service vulnerability in F5 BIG-IP where undisclosed HTTP requests targeting a virtual server protected by BIG-IP Advanced WAF or ASM security policy cause the bd (bigd) process to terminate. The bd process handles WAF/ASM functionality, and its termination disrupts security policy enforcement.

MitigationApply the vendor-supplied patch or upgrade to a fixed BIG-IP version when available. Until then, consider implementing rate limiting or request filtering at upstream devices to reduce exposure to the unknown attack vector.

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 Application Security ManagerApplication
Affected:>= 16.1.0, <= 16.1.6>= 17.1.0, <= 17.1.3>= 17.5.0, <= 17.5.1= 21.0.0
Big Ip Advanced Web Application FirewallApplication
Affected:>= 16.1.0, <= 16.1.6>= 17.1.0, <= 17.1.3>= 17.5.0, <= 17.5.1= 21.0.0

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
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

CVSS:3.1/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. Check BIG-IP version
    Run 'tmsh show sys version' or 'bigstart status' to determine the installed BIG-IP version. Compare against affected ranges: 16.1.0-16.1.6, 17.1.0-17.1.3, 17.5.0-17.5.1, 21.0.0
    Affected if Version matches any of the affected ranges (16.1.0-16.1.6, 17.1.0-17.1.3, 17.5.0-17.5.1, or 21.0.0)
  2. Verify ASM or Advanced WAF module is provisioned
    Run 'tmsh list sys provision module' to list provisioned modules. Check if 'asm' or 'afm' (Advanced WAF) appears with a provision level other than 'none'
    Affected if ASM or Advanced WAF module is provisioned on the BIG-IP device
  3. Identify virtual servers with WAF security policies
    Run 'tmsh list ltm virtual' and look for the 'security-nat-policy' or 'policy' fields referencing ASM/Advanced WAF policies. Alternatively, check via Configuration Utility under Local Traffic > Virtual Servers
    Affected if Any virtual server has an ASM or Advanced WAF security policy applied
  4. Check bd process status and logs
    Run 'bigstart status bd' to check if the bigd/bd process is running. Review /var/log/ltm for 'bd' or 'bigd' process termination events using 'grep -i bd /var/log/ltm'
    Affected if The bd process has terminated or is not running, especially after receiving unusual HTTP traffic
  5. Confirm security policy is in blocking mode
    Run 'tmsh list asm policy' and check the 'enforcement-mode' setting. Also check the virtual server security policy configuration
    Affected if A security policy is actively enforced (not in transparent or learning mode) on a protected virtual server

You are affected if you run an affected BIG-IP version (16.1.x, 17.1.x, 17.5.x, or 21.0.0) with ASM or Advanced WAF module provisioned and a security policy applied to a virtual server receiving HTTP traffic.

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 a release after 17.5.1
Interim mitigation

Apply the vendor-supplied patch or upgrade to a fixed BIG-IP version when available. Until then, consider implementing rate limiting or request filtering at upstream devices to reduce exposure to the unknown attack vector.

Recommended fix Moderate confidence

BIG-IP 16.1.7+ (16.1.x), 17.1.4+ (17.1.x), 17.5.2+ (17.5.x), or 21.0.1+ (21.0.x) - whichever corresponds to your current major version branch

  1. 1. Identify the currently deployed BIG-IP ASM or Advanced WAF version using 'tmsh show sys version' or the web management console.
  2. 2. For BIG-IP 16.1.x deployments (16.1.0-16.1.6): Upgrade to BIG-IP 16.1.7 or later stable 16.1.x release.
  3. 3. For BIG-IP 17.1.x deployments (17.1.0-17.1.3): Upgrade to BIG-IP 17.1.4 or later stable 17.1.x release.
  4. 4. For BIG-IP 17.5.x deployments (17.5.0-17.5.1): Upgrade to BIG-IP 17.5.2 or later stable 17.5.x release.
  5. 5. For BIG-IP 21.0.0 deployments: Upgrade to BIG-IP 21.0.1 or later stable 21.0.x release.
  6. 6. After upgrade, verify the bd (bigd) process stability and confirm the security policy functions correctly.
  7. 7. Test the ASM/Advanced WAF policy in a staging environment before deploying to production.
Caveat Review F5 release notes for your target version for potential configuration or behavioral changes; always test in non-production first

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

Fix this in Big Ip Application Security Manager Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA1.0 h
10.0 hours of engineering $1,750
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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-2026-40060 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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