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TXT Record XSS

who.is

61–70 of 236 posts

Re: TXT Record XSS

#61
post #57

I am half serious, but how about making HTML served in TXT records a standard trick for serving small web pages very quickly? There are way fewer network round trips: 1. DNS query for TXT record for example.com 2. DNS reply with HTML content Compared with the traditional 7 steps: 1. DNS query for A record for example.com 2. DNS reply with x.x.x.x 3. TCP SYN to port 80 4. TCP SYN/ACK 5. TCP ACK 6. HTTP GET 7. HTTP rep…

Use the Kitchen Sink[1] record type. It's more appropriated than TXT.

[1] https://tools.ietf.org/html/draft-ietf-dnsind-kitchen-sink-0...

Re: TXT Record XSS

#64
post #58

When I went to the page, it started playing music. I find that very frustrating and annoying.

That's the point--who.is won't play music by itself. Its lookup of the DNS records of jaimehawkins.co.uk injected the music into the page.

Yeah... that was actually hugely annoying. A little warning maybe.

Re: TXT Record XSS

#65
post #58

When I went to the page, it started playing music. I find that very frustrating and annoying.

That's the point--who.is won't play music by itself. Its lookup of the DNS records of jaimehawkins.co.uk injected the music into the page.

Oh I see. This makes sense. This doesn't seem challenging to prevent. A simple replacement of characters on the HTML entity table would have prevented this instead of putting arbitrary text onto standard output.

Re: TXT Record XSS

#66
post #57

I am half serious, but how about making HTML served in TXT records a standard trick for serving small web pages very quickly? There are way fewer network round trips: 1. DNS query for TXT record for example.com 2. DNS reply with HTML content Compared with the traditional 7 steps: 1. DNS query for A record for example.com 2. DNS reply with x.x.x.x 3. TCP SYN to port 80 4. TCP SYN/ACK 5. TCP ACK 6. HTTP GET 7. HTTP rep…

Meh, interesting thought, but a few things come to mind:

- It could take multiple days to update the website for the entire world

- It would be very easy to spoof the entire site

- It would probably slow down the rest of the queries the DNS server would be responding to at the time.

Also, updating DNS can be a pain for sites that aren't managing their own records.

Re: TXT Record XSS

#67

This is hilariousy, but could this potentially be a real threat to anything ?

Just wait until somebody turn it into a xargs bomb.

But yes, XSS is a serious problem. Even if it's done in a site that handles no valuable info (sites that display whois normaly handle very valuable info), it can be used to launch attacks against other sites.

Re: TXT Record XSS

#69
post #57

I am half serious, but how about making HTML served in TXT records a standard trick for serving small web pages very quickly? There are way fewer network round trips: 1. DNS query for TXT record for example.com 2. DNS reply with HTML content Compared with the traditional 7 steps: 1. DNS query for A record for example.com 2. DNS reply with x.x.x.x 3. TCP SYN to port 80 4. TCP SYN/ACK 5. TCP ACK 6. HTTP GET 7. HTTP rep…

Use the Kitchen Sink[1] record type. It's more appropriated than TXT. [1] https://tools.ietf.org/html/draft-ietf-dnsind-kitchen-sink-0...

I saw "ASN.1" in the draft and immediately thought "over-engineered".

Re: TXT Record XSS

#70
post #35

Wish there was a warning, because I accidentally clicked this link in class just now.

Always put your audio driver on mute when in class or in public setting.
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