dbcve.org
Web Security ApplianceApplication · Cisco

CVE-2016-1440

MEDIUM · 5.3 CVSS v3.0 Published 2016-07-02
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
62/100
Remediation priority · Elevated
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
The proxy process on Cisco Web Security Appliance (WSA) devices through 9.1.0-070 allows remote attackers to cause a denial of service (CPU consumption) by establishing an FTP session and then improperly terminating the control connection after a file transfer, aka Bug ID CSCuy43468.

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

A denial of service vulnerability exists in the proxy process of Cisco Web Security Appliance devices through version 9.1.0-070. Attackers can trigger excessive CPU consumption by establishing an FTP session and then improperly terminating the control connection after completing a file transfer, causing the proxy to remain in a hung or resource-consuming state.

MitigationApply the Cisco security update for WSA to a version beyond 9.1.0-070. If immediate patching is not possible, consider restricting or monitoring FTP proxy traffic at network boundaries to detect and block malicious session termination patterns.

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
Web Security ApplianceApplication
Affected:= 5.6.0-623= 6.0.0-000= 7.1.0= 7.1.1= 7.1.2= 7.1.3= 7.1.4= 7.5.0-000= 7.5.0-825= 7.5.1-000= 7.5.2-000= 7.5.2-hp2-303

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
Low

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 Cisco WSA device version
    Access the WSA CLI or web interface and retrieve the current firmware version. In CLI, this is typically done with the 'version' command or by checking the System Administration > Software Updates page in the web UI.
    Affected if The installed version is 9.1.0-070 or any version lower than 9.1.0-070 (such as 7.5.2-hp2-303, 7.5.2-000, 7.5.1-000, 7.5.0-825, 7.5.0-000, 7.1.4, 7.1.3, 7.1.2, 7.1.1, 7.1.0, 6.0.0-000, or 5.6.0-623).
  2. Verify FTP proxy service is enabled
    Check the WSA proxy configuration to confirm FTP proxy functionality is active. In the web UI, navigate to Security Services > FTP Proxy, or use the CLI command 'ftpproxy config' to view the FTP proxy settings.
    Affected if FTP proxy is enabled and the WSA version falls within the affected range.
  3. Inspect proxy process resource usage
    Monitor the proxy process CPU utilization using WSA CLI commands such as 'proxystat' or 'top', or examine system health via the web UI Dashboard. Look for abnormally high CPU consumption or proxy processes that appear hung or unresponsive.
    Affected if The proxy process is consuming excessive CPU resources or is in a hung state following incomplete FTP session terminations.

A Cisco Web Security Appliance is affected if it runs version 9.1.0-070 or lower, has FTP proxy enabled, and exhibits high CPU usage or hung proxy processes related to FTP session handling.

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 Cisco security update for WSA to a version beyond 9.1.0-070. If immediate patching is not possible, consider restricting or monitoring FTP proxy traffic at network boundaries to detect and block malicious session termination patterns.

Fix this in Web Security Appliance Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-1440 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2016-1440 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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