Firesight System SoftwareApplication · Cisco
CVE-2015-6427
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 · uneditedCisco FireSIGHT Management Center allows remote attackers to bypass the HTTP attack detection feature and avoid triggering Snort IDS rules via an SSL session that is mishandled after decryption, aka Bug ID CSCux53437.
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 confidenceCisco FireSIGHT Management Center has a vulnerability where SSL sessions are mishandled after decryption, allowing remote attackers to bypass the HTTP attack detection feature and avoid triggering Snort IDS rules. This enables malicious HTTP traffic embedded within properly decrypted SSL sessions to pass through undetected.
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
Firesight System SoftwareApplication
= 5.3.0= 5.3.0.1= 5.3.0.2= 5.3.1= 5.3.1.1= 5.3.1.2= 5.3.1.3= 5.3.1.4= 5.3.1.5= 5.3.1.7= 5.4.0= 5.4.0.1CVSS 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
- Authentication
- None
- Confidentiality
- None
- Integrity
- Partial
- Availability
- None
AV:N/AC:L/Au:N/C:N/I:P/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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Determine installed FireSIGHT System Software versionAccess the FireSIGHT Management Center web UI, navigate to System > Updates > System > RPM Version, or run 'show version' via CLI to identify the installed software versionAffected if The version matches any of these: 5.3.0, 5.3.0.1, 5.3.0.2, 5.3.1, 5.3.1.1, 5.3.1.2, 5.3.1.3, 5.3.1.4, 5.3.1.5, 5.3.1.7, 5.4.0, or 5.4.0.1
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Verify if SSL decryption policy is enabledIn the FMC web UI, navigate to Policies > SSL Policy to check whether an SSL decryption policy is applied to any access control rule or policyAffected if SSL decryption is enabled and traffic is being decrypted by the FireSIGHT system
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Confirm HTTP attack detection is activeCheck that Snort-based HTTP intrusion rules are enabled in the intrusion policy applied to the traffic. In FMC, go to Policies > Intrusion > Policy and verify rules are loaded for HTTP traffic inspectionAffected if Intrusion detection policies with HTTP rules are actively inspecting traffic that passes through the decrypted SSL sessions
You are affected if you run any of the listed versions AND have SSL decryption enabled with HTTP intrusion detection active, as the vulnerability allows malicious HTTP traffic in decrypted SSL sessions to bypass Snort IDS rules.
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 dataApply the vendor patch from Cisco for Bug ID CSCux53437 through the standard FireSIGHT/FMC update mechanism and verify that Snort IDS rules properly trigger on decrypted HTTP traffic.
Fix this in Firesight System Software
Scoped from the published advisory
- Consultation2.0 h
- Implementation3.0 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 $3,040.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2015-6427 — 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-2015-6427 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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