fix sensitive_data redaction order to prevent substring leaks (#4660)

Resolves #4609

<!-- This is an auto-generated description by cubic. -->
---
## Summary by cubic
Fixes #4609 by preventing substring leaks during sensitive data
redaction. Redaction now replaces longer secrets first and uses shared
utils for consistent behavior.

- **Bug Fixes**
  - Redact longest matches first to avoid partial/substring leaks.
  - Support both legacy flat and domain-scoped `sensitive_data` formats.
  - Apply consistent redaction across message manager and views.

- **Refactors**
- Added `collect_sensitive_data_values` and `redact_sensitive_string` in
`browser_use/utils.py`.
- Replaced inline redaction logic in
`browser_use/agent/message_manager/service.py` and
`browser_use/agent/views.py`.

<sup>Written for commit 65f87b7fca.
Summary will update on new commits.</sup>

<!-- End of auto-generated description by cubic. -->

browser_use/agent/message_manager/service.py

@@ -25,7 +25,12 @@ from browser_use.llm.messages import (
 	UserMessage,
 )
 from browser_use.observability import observe_debug
-from browser_use.utils import match_url_with_domain_pattern, time_execution_sync
+from browser_use.utils import (
+	collect_sensitive_data_values,
+	match_url_with_domain_pattern,
+	redact_sensitive_string,
+	time_execution_sync,
+)
 
 logger = logging.getLogger(__name__)
 
@@ -573,30 +578,14 @@ class MessageManager:
 			if not self.sensitive_data:
 				return value
 
-			# Collect all sensitive values, immediately converting old format to new format
-			sensitive_values: dict[str, str] = {}
-
-			# Process all sensitive data entries
-			for key_or_domain, content in self.sensitive_data.items():
-				if isinstance(content, dict):
-					# Already in new format: {domain: {key: value}}
-					for key, val in content.items():
-						if val:  # Skip empty values
-							sensitive_values[key] = val
-				elif content:  # Old format: {key: value} - convert to new format internally
-					# We treat this as if it was {'http*://*': {key_or_domain: content}}
-					sensitive_values[key_or_domain] = content
+			sensitive_values = collect_sensitive_data_values(self.sensitive_data)
 
 			# If there are no valid sensitive data entries, just return the original value
 			if not sensitive_values:
 				logger.warning('No valid entries found in sensitive_data dictionary')
 				return value
 
-			# Replace all valid sensitive data values with their placeholder tags
-			for key, val in sensitive_values.items():
-				value = value.replace(val, f'<secret>{key}</secret>')
-
-			return value
+			return redact_sensitive_string(value, sensitive_values)
 
 		if isinstance(message.content, str):
 			message.content = replace_sensitive(message.content)

browser_use/agent/views.py

@@ -27,6 +27,7 @@ from browser_use.filesystem.file_system import FileSystemState
 from browser_use.llm.base import BaseChatModel
 from browser_use.tokens.views import UsageSummary
 from browser_use.tools.registry.views import ActionModel
+from browser_use.utils import collect_sensitive_data_values, redact_sensitive_string
 
 logger = logging.getLogger(__name__)
 
@@ -512,29 +513,13 @@ class AgentHistory(BaseModel):
 		if not sensitive_data:
 			return value
 
-		# Collect all sensitive values, immediately converting old format to new format
-		sensitive_values: dict[str, str] = {}
-
-		# Process all sensitive data entries
-		for key_or_domain, content in sensitive_data.items():
-			if isinstance(content, dict):
-				# Already in new format: {domain: {key: value}}
-				for key, val in content.items():
-					if val:  # Skip empty values
-						sensitive_values[key] = val
-			elif content:  # Old format: {key: value} - convert to new format internally
-				# We treat this as if it was {'http*://*': {key_or_domain: content}}
-				sensitive_values[key_or_domain] = content
+		sensitive_values = collect_sensitive_data_values(sensitive_data)
 
 		# If there are no valid sensitive data entries, just return the original value
 		if not sensitive_values:
 			return value
 
-		# Replace all valid sensitive data values with their placeholder tags
-		for key, val in sensitive_values.items():
-			value = value.replace(val, f'<secret>{key}</secret>')
-
-		return value
+		return redact_sensitive_string(value, sensitive_values)
 
 	def _filter_sensitive_data_from_dict(
 		self, data: dict[str, Any], sensitive_data: dict[str, str | dict[str, str]] | None

browser_use/utils.py

@@ -31,6 +31,30 @@ _openai_bad_request_error: type | None = None
 _groq_bad_request_error: type | None = None
 
 
+def collect_sensitive_data_values(sensitive_data: dict[str, str | dict[str, str]] | None) -> dict[str, str]:
+	"""Flatten legacy and domain-scoped sensitive data into placeholder -> value mappings."""
+	if not sensitive_data:
+		return {}
+
+	sensitive_values: dict[str, str] = {}
+	for key_or_domain, content in sensitive_data.items():
+		if isinstance(content, dict):
+			for key, val in content.items():
+				if val:
+					sensitive_values[key] = val
+		elif content:
+			sensitive_values[key_or_domain] = content
+
+	return sensitive_values
+
+
+def redact_sensitive_string(value: str, sensitive_values: dict[str, str]) -> str:
+	"""Replace sensitive values with placeholders, longest matches first to avoid partial leaks."""
+	for key, secret in sorted(sensitive_values.items(), key=lambda item: len(item[1]), reverse=True):
+		value = value.replace(secret, f'<secret>{key}</secret>')
+	return value
+
+
 def _get_openai_bad_request_error() -> type | None:
 	"""Lazy loader for OpenAI BadRequestError."""
 	global _openai_bad_request_error