SDK information logs can contain complete payment records, and reviewed wallets retain or forward those logs

What the evidence shows

Technical and product details

1. SDK behavior

   Breez logs the debug representation of a complete Payment at INFO when emitting a payment event. 1

   Supporting material shown on this page

   Breez payment-event loggingPinned source code · github.com · checked 2026-08-24

   59                warn!("Failed to fetch payment from storage: {e:?}");
   60                payment
   61            }
   62        };
   63    info!("Emitting payment event: {payment:?}");
   64    event_emitter.emit(&SdkEvent::from_payment(payment)).await;
   65}

2. Wallet behavior

   Blink forwards SDK INFO and WARN lines to Firebase Crashlytics logging and records SDK ERROR lines as application errors. Cake subscribes to the SDK log stream and appends every received line to a local plaintext lightning.log file. 23

   Supporting material shown on this page

   Blink Crashlytics log forwardingPinned source code · github.com · checked 2026-08-24

   36const logDispatch: Record<SdkLogLevel, (msg: string) => void> = {
   37  [SdkLogLevel.Debug]: (msg) => console.debug(msg),
   38  [SdkLogLevel.Info]: (msg) => {
   39    console.debug(msg)
   40    crashlytics().log(msg)
   41  },

   Cake plaintext SDK logPinned source code · github.com · checked 2026-08-24

   104      _eventStream ??= sdk.addEventListener().asBroadcastStream();
   105      _logStream ??= initLogging().asBroadcastStream();
   106
   107      try {
   108        final logFile = File("$appPath/lightning.log")
   109          ..createSync();

Scope control

What this does not establish

• The code proves logging and forwarding paths, not that every line contains every field or that every Crashlytics line was uploaded. Cake's cited log is local unless another user or app action exports it. 123

Sources and excerpts

Primary sources

The relevant details and available source-code excerpts appear alongside the claims above. This list preserves the complete original-source trail for independent verification.