Web Security Virtual ApplianceApplication · Cisco
CVE-2015-6287
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 Web Security Appliance (WSA) 8.0.6-078 and 8.0.6-115 allows remote attackers to cause a denial of service (service outage) via a flood of TCP traffic that leads to DNS resolution delays, aka Bug IDs CSCur32005 and CSCur07907.
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 confidenceCisco Web Security Appliance versions 8.0.6-078 and 8.0.6-115 are vulnerable to a denial of service condition. An attacker can flood the appliance with TCP traffic, which causes DNS resolution delays and ultimately service outage. This is a resource exhaustion vulnerability where the appliance cannot properly handle the TCP flood in conjunction with DNS lookups.
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 Virtual ApplianceApplication
= 8.0.5= 8.0.6= 8.0_baseCVSS 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
- None
- Availability
- Partial
AV:N/AC:L/Au:N/C:N/I:N/A:P
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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Confirm Cisco WSA installationRun 'lsb_release -a' or check for WSA-specific processes/services on the system. On the appliance CLI, run 'version' to confirm it is a Cisco Web Security Appliance.Affected if The system is identified as a Cisco Web Security Appliance.
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Check WSA software versionOn the WSA CLI, run the 'version' command to display the installed AsyncOS version. Compare the version number to the affected ranges (8.0.5, 8.0.6, 8.0_base, specifically builds 8.0.6-078 and 8.0.6-115).Affected if The installed version is 8.0.5, 8.0.6, 8.0_base, or specifically build 8.0.6-078 or 8.0.6-115.
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Verify network exposure to untrusted TCP trafficReview network configuration to determine if the WSA management or proxy interfaces are directly accessible from untrusted networks. Check firewall rules and interface bindings using 'interfaceconfig' on the WSA CLI.Affected if The WSA TCP ports (proxy ports 80/443, DNS, or management) are exposed to unauthenticated network attackers.
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Check for DNS service configurationOn the WSA CLI, run 'dnsconfig' to review configured DNS servers. The vulnerability triggers when TCP flood occurs alongside DNS lookups.Affected if DNS is configured and active on the appliance, making it susceptible to the resource exhaustion condition.
A user is affected if they are running Cisco Web Security Appliance version 8.0.5, 8.0.6, or 8.0_base (specifically builds 8.0.6-078 or 8.0.6-115) with network exposure to untrusted TCP traffic and DNS resolution enabled.
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 appropriate Cisco software update/patch for WSA to address the vulnerability. In the interim, implement network-level traffic filtering or rate limiting to mitigate TCP flood attacks targeting the appliance.
Fix this in Web Security Virtual Appliance
Scoped from the published advisory
- Consultation3.0 h
- Implementation4.0 h
- Testing3.0 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 $3,408.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2015-6287 — 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-2015-6287 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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