1621729 - privacy.resistFingerprinting set to true breaks login at https://appleid.apple.com

Status: RESOLVED WORKSFORME

(Core :: DOM: Security, defect, P2)

Description

[crssi]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:68.0) Gecko/20100101 Firefox/68.0

Steps to reproduce:

privacy.resistFingerprinting set to true

Visit https://appleid.apple.com to sign in.

Actual results:

SIgn-in part does not load.

Expected results:

Sign-in part should load.

Comment 1

[Ethan Tseng [:ethan]]

Attachment: resistFingerprintingIsOn.png

Comment 2

[Ethan Tseng [:ethan]]

Attachment: resistFingerprintingIsOff.png

Comment 3

[Ethan Tseng [:ethan]]

Tom and Tim, have we seen this kind of breakage in the past? Do you have ideas on why resistFingerprinting would cause this problem?

Comment 4

[Tom Ritter [:tjr]]

They're calling window.performance.getEntriesByName() and assuming it will return values and then indexing into the result (which has no values.) This causes a JavaScript error and the page breaks and stops loading.

Comment 5

[Tom Ritter [:tjr]]

No promises, but I'm told that we will let Apple know about this issue and perhaps they will fix it.

Apple engineer who winds up on this page: Here is our behavior. To test:

1. go to about:config
2. search for privacy.resistFingerprinting and set it to True

Comment 6

[Peter Saint-Andre [:stpeter]]

I've reached out to a contact at Apple about this.

Comment 7

[Ethan Tseng [:ethan]]

(In reply to Peter Saint-Andre [:stpeter] from comment #6)

I've reached out to a contact at Apple about this.

Did they respond that they'll fix their website as Tom mentioned?

Comment 8

[Kestrel]

https://www.svtplay.se is also similarly broken by perfomance API spoofing (website fails to load).

TypeError: "can't access property "duration", window.performance.getEntriesByName(...)[0] is undefined"

Comment 9

[Peter Saint-Andre [:stpeter]]

(In reply to Ethan Tseng [:ethan] from comment #7)

(In reply to Peter Saint-Andre [:stpeter] from comment #6)

I've reached out to a contact at Apple about this.

Did they respond that they'll fix their website as Tom mentioned?

My contact is figuring out how to route this issue at Apple.

Comment 10

[crssi]

Peter, did your contact figured out how to route this issue to Apple?

Comment 11

[Ben Montour]

This is still an issue in FF 78.0.2. Is this something that could be brought up with the WebCompat team to work with Apple on?

Comment 13

[crssi]

After a 7 months this is stil an issue on FF 81.0.1.

Can't believe that apple login is closed and set as a duplicate to some porn stuff.
I see it as is discourage for future bug reporting.

Comment 14

[Kestrel]

Sorry, my mistake and thanks for confirming it is still an issue. Bug 1637985 looks like it should have fixed the issue mentioned in Comment 4 in FF 79 and my Comment 8 test case with a similar problem now works but the apple login is still broken:

Uncaught TypeError: can't access property "startTime", d[(d.length - 1)] is undefined

Comment 15

[Thorin [:thorin]]

RFP off, array is populated
RFP on, array is empty

.measure should return results with 100ms precision or something like that

https://developer.mozilla.org/en-US/docs/Web/API/Performance/measure

	try {
		const markerNameA = "example-marker-a"
		const markerNameB = "example-marker-b"
		performance.mark(markerNameA)
		setTimeout(function() {
			performance.mark(markerNameB)
			setTimeout(function() {
				// create
				performance.measure("measure a to b", markerNameA, markerNameB)
				performance.measure("measure a to now", markerNameA)
				performance.measure("measure from navigation start to b", undefined, markerNameB)
				performance.measure("measure from navigation start to now")
				// console
				console.log(performance.getEntriesByType("measure"))
				// cleanup
				performance.clearMarks()
				performance.clearMeasures()
			}, 20)
		}, 10)
	} catch(e) {
		console.error(e.name, e.message)
	}

Comment 16

[Thorin [:thorin]]

hotels.com with RFP enabled

   TypeError: can't access property "startTime", o.performanceMetrics.findMark(...) is undefined

Comment 17

[Thorin [:thorin]]

Word Press / OpenWeb comments (if you block wp.com the error does not occur)

• test: https://techcrunch.com/2022/05/05/amazon-labor-senate-christian-smalls-bernie-sanders/
• also: https://old.reddit.com/r/LibreWolf/comments/ujocnk/openweb_comments_broken/

 TypeError: can't access property "duration", v is undefined

Comment 18

[Fabrizio]

nike.com logins breaks when RFP is on.

Steps to reproduce:

• create an account (I used a disposable email like firefox relay)
• enable RFP
• try to login

Result:

• an error message is shown, as well as a failed POST request in the console with output:

Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://unite.nike.com/login?...

(Reason: CORS header ‘Access-Control-Allow-Origin’ missing)

If I disable RFP I can login just fine.

Comment 19

[Fabrizio]

https://www.travelocity.com/ has a similar behavior to https://bugzilla.mozilla.org/show_bug.cgi?id=1621729#c16. With RFP on:

TypeError: o.performanceMetrics.findMark(...) is undefined
Cross-Origin Request Blocked: The Same Origin Policy disallows reading the remote resource at https://oms.expedia.com/b/ss/expediaglobal/10/JS-2.6.0/s77722092331113. (Reason: CORS request did not succeed). Status code: (null).

Comment 20

[Fabrizio]

twitch.tv logins are broken on Linux when RFP is on.

Steps to reproduce when using Firefox on Linux:

• enable RFP
• try to login

Result:

• an error is shown, saying the browser is not supported
• https://passport.twitch.tv/integrity is the check, it sets a 7 day cookie that prevents subsequent logins even with RFP disabled (unless the cookie is cleared)

Notes:

• the issue doesn't occur on macOS even with RFP enabled
• testing doesn't require an account, random credentials are fine because on macOS it shows "invalid password" while on Linux it says the browser is not supported
• the issue can be reproduced by enabling RFP on macOS and spoofing the Navigator API to Linux (I used Canvas Blocker for this test)

Comment 21

[Kestrel]

Fixed by Bug 1811567: speed.cloudflare.com, zillow.com, expedia.com, hotels.com, travelocity.com, bazaarvoice.com reviews, openweb.com comments.

Already working: svtplay.se, appleid.apple.com.

Still not working: twitch.tv login, nike.com login (Bug 1805101).