Zope AccessControl provides a general security framework for use in Zope. Prior to 7.4, applications that allow untrusted users to create and execute AccessControl-controlled Python code do not safely guard str.format and str.format_map when those methods are reached through a str subclass. In both ImplPython.py and cAccessControl.c, Python formatting can recursively access attributes and subscriptions using unrestricted getattr and getitem behavior instead of the policy-restricted getattr and getitem operations.
A controlled format string can therefore disclose objects reachable from values available to the formatting operation. This issue is fixed in version 7.4.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
High
Admin privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption
CVSS Vector v3.1
Weakness Type (CWE)
References 3
https://github.com/zopefoundation/AccessControl/commit/f980450eea416718be62847f…
security-advisories@github.com
https://github.com/zopefoundation/AccessControl/releases/tag/7.4
security-advisories@github.com
https://github.com/zopefoundation/AccessControl/security/advisories/GHSA-pq59-9…
security-advisories@github.com