FortiosOperating system · Fortinet
CVE-2016-8492
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 · uneditedThe implementation of an ANSI X9.31 RNG in Fortinet FortiGate allows attackers to gain unauthorized read access to data handled by the device via IPSec/TLS decryption.
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 confidenceFortiGate devices contain a weak implementation of the ANSI X9.31 random number generator that allows attackers to gain unauthorized read access to decrypted data passing through IPSec VPN tunnels or TLS connections. The compromised RNG can expose sensitive data that should be protected by encryption.
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
FortiosOperating system
<= 4.3.18= 4.3.0= 4.3.10= 4.3.12= 4.3.13= 4.3.14= 4.3.15= 4.3.16= 4.3.17CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 versionAccess the FortiGate CLI and run the command 'get system status' or 'show system global' to retrieve the firmware version. Alternatively, check from the web UI under Dashboard > Status.Affected if The displayed FortiOS version is 4.3.0, 4.3.10, 4.3.12, 4.3.13, 4.3.14, 4.3.15, 4.3.16, 4.3.17, or any version <= 4.3.18.
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Verify IPSec VPN configurationRun 'show ipsec phase1' and 'show ipsec phase2' in the FortiGate CLI to list configured IPSec tunnels. Run 'get vpn ipsec status' to see active tunnel status.Affected if Any IPSec phase1 or phase2 interfaces are configured or active on a FortiOS version within the affected range.
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Verify SSL-VPN or TLS inspection is configuredRun 'show ssl vpn' or 'show ssl vpn global' in the CLI. For TLS inspection, run 'show policy' and look for SSL/SSH inspection policies.Affected if Any SSL-VPN, TLS inspection, or deep inspection policies are configured on a FortiOS version within the affected range.
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Check for TLS server certificatesRun 'show system interface' and examine the port1 or internal interface settings. Run 'get system interface' to list all interfaces and their IPsec/SSL-VPN bindings.Affected if SSL-VPN web mode or tunnel mode is enabled, or TLS inspection is active on a device running an affected FortiOS version.
You are affected if your FortiGate runs FortiOS 4.3.x version 4.3.18 or lower and has IPSec VPN tunnels or SSL-VPN/TLS inspection actively configured or in use.
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 dataUpgrade FortiGate firmware to the latest version that includes the patched RNG implementation. After upgrading, consider rekeying IPSec tunnels and regenerating TLS certificates as a precautionary measure.
Fix this in Fortios
Scoped from the published advisory
- Consultation4.0 h
- Implementation8.0 h
- Testing12.0 h
- Review / QA4.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $7,616.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2016-8492 — 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-2016-8492 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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- Verified mitigations, workarounds, and config changes
- Version or environment caveats, and links to real fixes
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