Secure Firewall Management CenterApplication · Cisco
CVE-2020-3315
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 · uneditedMultiple Cisco products are affected by a vulnerability in the Snort detection engine that could allow an unauthenticated, remote attacker to bypass the configured file policies on an affected system. The vulnerability is due to errors in how the Snort detection engine handles specific HTTP responses. An attacker could exploit this vulnerability by sending crafted HTTP packets that would flow through an affected system. A successful exploit could allow the attacker to bypass the configured file policies and deliver a malicious payload to the protected network.
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 confidenceThis vulnerability exists in Cisco products using the Snort detection engine. The flaw in how Snort handles specific HTTP responses allows attackers to craft packets that bypass configured file policies, potentially delivering malicious payloads to protected networks.
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
Secure Firewall Management CenterApplication
= 2.9.14.4= 2.9.15= 2.9.16
Secure Firewall Threat DefenseApplication
< 6.6.0
iOSApplication
= 15.2\(7\)e= 16.11.2= 17.3.1CVSS 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
- Low
- Availability
- None
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/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 your Cisco product and versionUse 'show version' on the device CLI or access the management console to determine if you are running Cisco Firepower Threat Defense, Cisco Secure Firewall Management Center, or Cisco iOS, and record the exact version number.Affected if The product is one of: Firepower Threat Defense, Secure Firewall Management Center, or Cisco iOS with a version matching the affected ranges.
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Verify Snort detection engine is enabledAccess the Firepower or Firewall management interface and check the intrusion policy settings. On CLI, use 'show snort' or check the policy configuration to confirm the Snort detection engine is active.Affected if Snort detection engine is enabled and processing traffic.
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Confirm file inspection policies are configuredCheck the file policy settings in the Firepower or Secure Firewall Management Center under the Access Control or Intrusion Policy settings. Look for any File Policy or File Inspection configurations that inspect HTTP traffic.Affected if File policies for HTTP response inspection are configured.
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Check Snort engine versionIn the management center, navigate to System > Updates > Snort HD Update or use 'show snort version' command to determine the installed Snort detection engine version.Affected if The Snort engine version is earlier than the patched version for your product.
You are affected if your Cisco product and version match the affected ranges AND Snort with file policies is enabled, allowing crafted HTTP responses to potentially bypass inspection.
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 data6.6.0
Apply relevant Cisco patches for affected products and ensure Snort detection engine is updated to the latest version. Review and verify that file inspection policies are functioning correctly after updates.
Fix this in Secure Firewall Management Center
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-2020-3315 — 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-2020-3315 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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