CVE-2021-32807 – accesscontrol

Package

Manager: pip
Name: accesscontrol
Vulnerable Version: >=4.0 <4.3 || >=5.0 <5.2

Severity

Level: Medium

CVSS v3.1: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:N

CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS: 0.01883 pctl0.8245

Details

Remote Code Execution via unsafe classes in otherwise permitted modules ### Impact The module `AccessControl` defines security policies for Python code used in restricted code within Zope applications. Restricted code is any code that resides in Zope's object database, such as the contents of `Script (Python)` objects. The policies defined in `AccessControl` severely restrict access to Python modules and only exempt a few that are deemed safe, such as Python's `string` module. However, full access to the `string` module also allows access to the class `Formatter`, which can be overridden and extended within `Script (Python)` in a way that provides access to other unsafe Python libraries. Those unsafe Python libraries can be used for remote code execution. By default, you need to have the admin-level Zope "Manager" role to add or edit `Script (Python)` objects through the web. Only sites that allow untrusted users to add/edit these scripts through the web - which would be a very unusual configuration to begin with - are at risk. ### Patches The problem has been fixed in AccessControl 4.3 and 5.2. Only AccessControl versions 4 and 5 are vulnerable, and only on Python 3, not Python 2.7. ### Workarounds A site administrator can restrict adding/editing `Script (Python)` objects through the web using the standard Zope user/role permission mechanisms. Untrusted users should not be assigned the Zope Manager role and adding/editing these scripts through the web should be restricted to trusted users only. This is the default configuration in Zope. ### For more information If you have any questions or comments about this advisory: * Open an issue in the [AccessControl issue tracker](https://github.com/zopefoundation/AccessControl/issues) * Email us at [security@plone.org](mailto:security@plone.org)

Metadata

Created: 2021-08-05T17:01:30Z
Modified: 2024-09-03T21:13:35Z
Source: https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/08/GHSA-qcx9-j53g-ccgf/GHSA-qcx9-j53g-ccgf.json
CWE IDs: ["CWE-1321", "CWE-915"]
Alternative ID: GHSA-qcx9-j53g-ccgf
Finding: F390
Auto approve: 1