eBay has a big fraud headache. They have a bunch of algorithms (from the pre-ML-hype days) that take a variety of inputs to determine whether a given transaction is fraudulent or not. Presence of remote login service on the user’s computer may tip the scale heavily in this calculation. Fraud detection is a necessary evil for all financial transaction companies in order to keep costs low for everyone else. If you’re w…
eBay is port scanning visitors to their website
41–50 of 148 posts
Re: eBay is port scanning visitors to their website
#42eBay has a big fraud headache. They have a bunch of algorithms (from the pre-ML-hype days) that take a variety of inputs to determine whether a given transaction is fraudulent or not. Presence of remote login service on the user’s computer may tip the scale heavily in this calculation. Fraud detection is a necessary evil for all financial transaction companies in order to keep costs low for everyone else. If you’re w…
This isn't a privacy protection, though, but a measure for accountability. That is, only the absence of data aggregation would still someone's worry about privacy.
Re: eBay is port scanning visitors to their website
#43Earlier quoted context omitted.
irrc, eBay uses websocket connections [0] to scan the ports. Firefox doesn't offer an option to disable websockets in the about:config page. However, I have read about workarounds by setting network.websocket.max-connections=0 This is a global setting and is applied to all websites. I also wasn't able to test this myself yet. Are there any good extensions for blocking websockets on for specific domains? [0] https://n…
To people reading this, many websites rely on websockets for real-time information. They would likely fallback to per-refresh HTTP requests, but it also may break a bunch of sites.
If IT admins get wind of this they'll just block it (or never unblock it since it's been blocked by some from day 1) and our product gets degraded experience.
Re: eBay is port scanning visitors to their website
#44eBay has a big fraud headache. They have a bunch of algorithms (from the pre-ML-hype days) that take a variety of inputs to determine whether a given transaction is fraudulent or not. Presence of remote login service on the user’s computer may tip the scale heavily in this calculation. Fraud detection is a necessary evil for all financial transaction companies in order to keep costs low for everyone else. If you’re w…
Re: eBay is port scanning visitors to their website
#45This might explain why some preinstalled HP laptop software (with open ports?) causes a BSOD when users visit ebay https://h30434.www3.hp.com/t5/Notebook-Operating-System-and-...
Re: eBay is port scanning visitors to their website
#46Earlier quoted context omitted.
I don't understand this could you explain?
Ratings are an important part of the eBay ecosystem. He's saying people let others use their eBay accounts through RDC to game the system. Also it's an auction site. People want to raise the price by bidding on their own items
So let's we have fraudseller_1 that sell something like iPhone. Here comes honestbuyer_1 that bid for this item with $50. Seller sees offer, but want to rise it.
Since seller can't use his own IP he is using some remote desktop to login somewhere else as fraudbuyer_1 (different account!) and bid $100. Then he wait honestbuyer_1 to bid again. If this happens then two - fraudbuyer_1 and honestbuyer_1 can "race" (note the quotes!) for this item.
Of course this is simplified scenario because can be involved pack of fraud buyers to fool buyers.
I know some person IRL that was involved 10 years ago in such activities. So his friend sells vacation homes and buyers from UK bidding for them. But if seller doesn't like bids he call to that person to make bid from his own account. And of course to rise price with least $1000.
But... this can't be track using eBay since it's via phone call and no remote sessions. Today sellers using virtual desktops (RDP, VNC, TeamViewer or other) to do this.
Re: eBay is port scanning visitors to their website
#47Earlier quoted context omitted.
As far as I know these port scans are done using WebRTC. Using a browser extension[0] it is easy to deactivate it on the go. Personally, I always have WebRTC disabled by default (as it has several nasty security implications), and only activate it if I explicitly need it for something. [0] https://addons.mozilla.org/en-US/firefox/addon/happy-bonobo-...
irrc, eBay uses websocket connections [0] to scan the ports. Firefox doesn't offer an option to disable websockets in the about:config page. However, I have read about workarounds by setting network.websocket.max-connections=0 This is a global setting and is applied to all websites. I also wasn't able to test this myself yet. Are there any good extensions for blocking websockets on for specific domains? [0] https://n…
Ebay will have your IP from your request so they can run nmap against your machine from their server without your browser ever knowing about it.
I also know of a bank that does similar via an old school sort of way, their online banking login page tries to load images from urls made up of your IP and various ports.
Presumably these are targeting known ports for online banking malware C&C http traffic rather than remote desktop services though.
And this is a bank that still uses frames 'for security', so it must be an old technique!
Re: eBay is port scanning visitors to their website
#48Earlier quoted context omitted.
irrc, eBay uses websocket connections [0] to scan the ports. Firefox doesn't offer an option to disable websockets in the about:config page. However, I have read about workarounds by setting network.websocket.max-connections=0 This is a global setting and is applied to all websites. I also wasn't able to test this myself yet. Are there any good extensions for blocking websockets on for specific domains? [0] https://n…
Surely the websockets angle is a bit of a red herring? Ebay will have your IP from your request so they can run nmap against your machine from their server without your browser ever knowing about it. I also know of a bank that does similar via an old school sort of way, their online banking login page tries to load images from urls made up of your IP and various ports. Presumably these are targeting known ports for o…
They could still portscan from afar and it would still be sketchy, but using Websockets makes it worse
Re: eBay is port scanning visitors to their website
#49I asked this earlier and nobody had a response, so thought I'd ask it again: is there an extension to block this? Edit: @Windows users: pip install pydivert and then try to write a script to block connections from Chrome to non-Chrome processes. you might need GetTcpTable2() or something. (Looking into this now. Check out http://stackoverflow.com/a/25431340 )
Re: eBay is port scanning visitors to their website
#50Earlier quoted context omitted.
To people reading this, many websites rely on websockets for real-time information. They would likely fallback to per-refresh HTTP requests, but it also may break a bunch of sites.
As a developer on a product that uses websocket extensively, I'm afraid that this will lead to the already huge distrust in the technology. If IT admins get wind of this they'll just block it (or never unblock it since it's been blocked by some from day 1) and our product gets degraded experience.