Linksys Wrt54gx Router FirmwareApplication · Cisco
CVE-2011-4500
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 UPnP IGD implementation on the Cisco Linksys WRT54GX with firmware 2.00.05, when UPnP is enabled, configures the SOAP server to listen on the WAN port, which allows remote attackers to administer the firewall via SOAP requests.
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 confidenceThe Cisco Linksys WRT54GX firmware 2.00.05 incorrectly configures the UPnP IGD SOAP server to listen on the WAN (external) interface when UPnP is enabled. This exposes the UPnP management interface to the public internet, allowing remote attackers to send SOAP requests to manipulate firewall rules and potentially bypass security controls.
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
Linksys Wrt54gx Router FirmwareApplication
= 2.00.05= 2.0CVSS 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
- Partial
- Integrity
- Partial
- Availability
- Partial
AV:N/AC:L/Au:N/C:P/I:P/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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Identify router modelCheck the device label or web interface to confirm it is a Cisco Linksys WRT54GX routerAffected if Device is not a Linksys WRT54GX model
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Check firmware versionAccess the router web interface (typically at 192.168.1.1) and navigate to Administration > Firmware Upgrade or Status page to view the firmware versionAffected if Firmware version is 2.00.05 or 2.0
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Verify UPnP is enabledIn the router web interface, go to Administration > UPnP and check if UPnP is turned onAffected if UPnP is enabled on the device
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Confirm UPnP WAN accessibilityFrom an external network (not behind the router), use a port scanner or netcat to attempt a TCP connection to port 5555 on the router's public WAN IP address: nc -zv <WAN_IP> 5555Affected if Port 5555 (or the configured UPnP SOAP port) is open and reachable from the WAN/internet
A user is affected if they own a Linksys WRT54GX router running firmware 2.00.05 or 2.0 with UPnP enabled and the UPnP SOAP service is exposed on the WAN interface (port 5555 accessible from the internet).
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 dataDisable UPnP on the affected device if not required, or apply any available firmware update. At minimum, block inbound SOAP/UPnP traffic (port 5555 typically) at the WAN interface using external firewall rules.
Fix this in Linksys Wrt54gx Router Firmware
Scoped from the published advisory
- Consultation2.0 h
- Implementation2.0 h
- Testing1.0 h
- Review / QA1.0 h
An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,744.
Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2011-4500 — 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-2011-4500 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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