AccessControl provides a general security framework for use in Zope. Python's "format" functionality allows someone controlling the format string to "read" objects accessible (recursively) via attribute access and subscription from accessible objects. Those attribute accesses and subscriptions use Python's full blown getattr
and getitem
, not the policy restricted AccessControl
variants _getattr_
and _getitem_
. This can lead to critical information disclosure. AccessControl
already provides a safe variant for str.format
and denies access to string.Formatter
. However, str.format_map
is still unsafe. Affected are all users who allow untrusted users to create AccessControl
controlled Python code and execute it. A fix has been introduced in versions 4.4, 5.8 and 6.2. Users are advised to upgrade. There are no known workarounds for this vulnerability.