Headline
CVE-2023-26145: fix: don't allow object paths that reference dunder-method attributes… · dgilland/pydash@6ff0831
This affects versions of the package pydash before 6.0.0. A number of pydash methods such as pydash.objects.invoke() and pydash.collections.invoke_map() accept dotted paths (Deep Path Strings) to target a nested Python object, relative to the original source object. These paths can be used to target internal class attributes and dict items, to retrieve, modify or invoke nested Python objects. Note: The pydash.objects.invoke() method is vulnerable to Command Injection when the following prerequisites are satisfied: 1) The source object (argument 1) is not a built-in object such as list/dict (otherwise, the init.globals path is not accessible) 2) The attacker has control over argument 2 (the path string) and argument 3 (the argument to pass to the invoked method) The pydash.collections.invoke_map() method is also vulnerable, but is harder to exploit as the attacker does not have direct control over the argument to be passed to the invoked function.
Expand Up @@ -178,6 +178,7 @@ def _base_get_item(obj, key, default=UNSET): def _base_get_object(obj, key, default=UNSET): value = _base_get_item(obj, key, default=UNSET) if value is UNSET: _raise_if_restricted_key(key) value = default try: value = getattr(obj, key) Expand All @@ -186,6 +187,13 @@ def _base_get_object(obj, key, default=UNSET): return value
def _raise_if_restricted_key(key): # Prevent access to dunder-methods since this could expose access to globals through leaky # attributes such as obj.__init__.__globals__. if len(key) > 4 and key.isascii() and key.startswith(“__”) and key.endswith(“__”): raise KeyError(f"access to restricted key {key!r} is not allowed")
def base_set(obj, key, value, allow_override=True): “"” Set an object’s `key` to `value`. If `obj` is a ``list`` and the `key` is the next available Expand Down Expand Up @@ -213,6 +221,7 @@ def base_set(obj, key, value, allow_override=True): obj[:] = (obj + [None] * key)[:key] obj.append(value) elif (allow_override or not hasattr(obj, key)) and obj is not None: _raise_if_restricted_key(key) setattr(obj, key, value)
return obj Expand Down
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This affects versions of the package pydash before 6.0.0. A number of pydash methods such as pydash.objects.invoke() and pydash.collections.invoke_map() accept dotted paths (Deep Path Strings) to target a nested Python object, relative to the original source object. These paths can be used to target internal class attributes and dict items, to retrieve, modify or invoke nested Python objects. **Note:** The pydash.objects.invoke() method is vulnerable to Command Injection when the following prerequisites are satisfied: 1) The source object (argument 1) is not a built-in object such as list/dict (otherwise, the __init__.__globals__ path is not accessible) 2) The attacker has control over argument 2 (the path string) and argument 3 (the argument to pass to the invoked method) The pydash.collections.invoke_map() method is also vulnerable, but is harder to exploit as the attacker does not have direct control over the argument to be passed to the invoked function.