FortiproxyApplication · Fortinet
CVE-2019-17656
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 · uneditedA Stack-based Buffer Overflow vulnerability in the HTTPD daemon of FortiOS 6.0.10 and below, 6.2.2 and below and FortiProxy 1.0.x, 1.1.x, 1.2.9 and below, 2.0.0 and below may allow an authenticated remote attacker to crash the service by sending a malformed PUT request to the server. Fortinet is not aware of any successful exploitation of this vulnerability that would lead to code execution.
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 confidenceA stack-based buffer overflow vulnerability exists in the HTTPD daemon of FortiOS 6.0.10 and below, 6.2.2 and below, and FortiProxy versions 1.0.x through 2.0.0. An authenticated remote attacker can crash the service by sending a malformed PUT request to the server, causing a denial of service condition.
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
FortiproxyApplication
>= 1.0.0, < 1.2.10>= 2.0.0, < 2.0.2
FortiosOperating system
<= 6.0.10>= 6.2.0, <= 6.2.2CVSS 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
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- None
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:L/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 checksWork through these to decide whether this CVE applies to you.
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Identify FortiOS versionLog into the FortiGate via CLI and run the command: get system status. Look for the version number in the output.Affected if The version displayed is 6.0.10 or below, OR falls between 6.2.0 and 6.2.2 inclusive.
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Identify FortiProxy versionLog into the FortiProxy via CLI and run the command: get system status. Look for the version number in the output.Affected if The version displayed is 1.0.0 or higher but below 1.2.10, OR is 2.0.0 or higher but below 2.0.2.
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Confirm HTTPD service is runningCheck via CLI command: get system status or diagnose sys service stat | grep httpd. The HTTPD daemon must be active for the vulnerability to be exploitable.Affected if The HTTPD service is running and accepting connections.
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Verify admin access exposureReview network access settings via: get system interface or show system accconsole. Determine if the management interface is accessible from untrusted networks.Affected if The admin or management interface is reachable from external or untrusted networks without proper access restrictions.
You are affected if your FortiOS version falls in the <=6.0.10 or 6.2.0-6.2.2 range, or your FortiProxy version is 1.0.0-1.2.9 or 2.0.0-2.0.1, and the HTTPD service is running with potential external access.
Generated from the published advisory. Verify against your own configuration.
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 data1.2.102.0.2
Apply the vendor-supplied patches for FortiOS and FortiProxy to the latest supported versions. Additionally, limit access to trusted authenticated users and restrict PUT request capabilities where possible to reduce the attack surface.
Fix this in Fortiproxy
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing4.0 h
- Review / QA2.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2019-17656 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2019-17656 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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