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Lax Cookie Not Sent in iFrame on 302 Redirection

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I’m building an Angular application that is using OAuth2 Auth Code w/PKCE. The app uses hidden iframes to silently renew access tokens. I found that when the OAuth2 authorization serve redirects the iFrame to {parent origin}/silent-refresh.html with a 302, Firefox does not send any cookies set with SameSite: Lax.

SameSite: None cookies are sent as expected.

I compared this with IE and Chrome and both of those browser send the Lax cookies on when redirecting due to a 302.

This problem seems to only occur when the iFrame is being redirected via 302 from a different origin. I.e requests from a basic iFrame to the parent page origin send Lax cookies with no problem.

Anyone experience this? Is this expected behavior for Firefox?

Firefox Version 68.8

I’m building an Angular application that is using OAuth2 Auth Code w/PKCE. The app uses hidden iframes to silently renew access tokens. I found that when the OAuth2 authorization serve redirects the iFrame to {parent origin}/silent-refresh.html with a 302, Firefox does not send any cookies set with SameSite: Lax. SameSite: None cookies are sent as expected. I compared this with IE and Chrome and both of those browser send the Lax cookies on when redirecting due to a 302. This problem seems to only occur when the iFrame is being redirected via 302 from a different origin. I.e requests from a basic iFrame to the parent page origin send Lax cookies with no problem. Anyone experience this? Is this expected behavior for Firefox? Firefox Version 68.8

All Replies (3)

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Does this also happen in current Firefox releases (current is 78.0.1) ?

There were some changes in Firefox 69.

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I’m working on getting a new version. My corporate version of Firefox comes bundled with some MFA software. So it hasn’t been as easy as just downloading the latest and retesting.

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Okay I was able to test this with 78.0.1 (64-bit) and the behavior is the same.