Visitor

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4 Messages

Friday, July 10th, 2026 11:48 PM

Inbound UDP packets not reaching bridged modem after Xfinity reprovisioning

My Xfinity service was reset/reprovisioned on April 29. Before that reset, inbound UDP traffic to my self-hosted server worked. After the reset, outside users can no longer use send packets via 10000/udp to my server.

This is not a Wi-Fi issue, speed issue, DNS issue, or customer-router configuration request.

Current setup:

Xfinity gateway in bridge mode
Firewalla router connected behind the gateway
Firewalla WAN receives the public IPv4 address directly
Server behind Firewalla
UDP 10000 port-forward rule exists on Firewalla to server.

LAN clients can send the packets to the server. Outside clients, including cellular, fail. I tested from an external IPVanish VPN to my ip on UDP destination port 10000. Firewalla shows zero hits on the UDP 10000 rule.

I also ran packet capture on the Firewalla/router side for UDP destination port 10000 during the external test, and no packets appeared.

Regular internet works and the modem signal may look good, but that does not test unsolicited inbound UDP delivery. I need this escalated beyond modem-health troubleshooting. Please have Tier 2, network/provisioning, or CSA verify whether unsolicited inbound UDP packets to my public IPv4 address are being filtered, dropped, or affected by security/provisioning before reaching my bridged modem/router handoff.

So far all techs only seem to have tools to test modem health.  I've even replaced the modem after I was promised escalation to the next group.  Now that is being refused since "the signal is good."  Customer requests Tier 2/network/provisioning/CSA review for possible filtering, security profile, or provisioning issue.  So far this request has fallen on deaf ears.  How can I get this request in front of someone that can restore the service to the way it worked on 4/27?

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Official Employee

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1.1K Messages

18 days ago

Hello, @user_f1a73a thank you for taking the time to reach out to us. Have you attempted to reach out to CSA at all? CSA does have a direct contact at this link. Customer security assurance

Visitor

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4 Messages

Yes I have.  I don't believe I've reached a person that understands the issue.  Every technician so far has tools to diagnose modem health, but this is not that type of issue.  The resolution sits inside one of these support towers, and I have been unable to get in front of someone that understands these concepts: account-level security filtering, 
abuse/CSA mitigation profile, 
network-edge/CMTS filtering, 
Advanced Security / xFi security state, 
provisioning state tied to the account or router MAC,
inbound unsolicited UDP being dropped before customer handoff.  I was given the direct number to them and another internet network department, but so far no help.  I'm also a little disturbed they keep closing the tickets and I have to start over and never make it to a proper person.

Official Employee

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338 Messages

@user_f1a73a  Sounds like I may need to take a closer look at your account.  Please follow the steps below to send a direct message. 

Please send us a direct chat message with your full name and complete service address to “Xfinity Support”. To do so, click on the chat icon located at the top right of this forum's page.

Here are the detailed steps to direct message us:

• Click "Sign In" if necessary

• Click the "Direct Message” icon (upper right corner of this page)

• Click the "New message" (pencil and paper) icon

• Type "Xfinity Support" in the "to" line and select "Xfinity Support" from the drop-down list

• Type your message in the text area near the bottom of the window

• Press Enter to send your message

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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Visitor

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4 Messages

Thank you I sent the direct message as you requested and will await your response.

Visitor

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4 Messages

Just to update, Xfinity has not be able to resolve this issue.  It is not apparent that they can have a tier 3 technician review this issue.

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