PYSEC-2026-4022
See a problem?- Import Source
- https://github.com/pypa/advisory-database/blob/main/vulns/accesscontrol/PYSEC-2026-4022.yaml
- JSON Data
- https://api.osv.dev/v1/vulns/PYSEC-2026-4022
- Aliases
- Published
- 2026-10-01T16:38:32Z
- Modified
- 2026-10-01T17:45:03Z
- Severity
-
- 6.8 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N CVSS Calculator
- Summary
- Zope AccessControl vulnerable to information disclosure through Python string `format` and `format_map` functions
- Details
-
Impact
Python's string
formatfunctionality 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 blowngetattrandgetitem, not the policy restrictedAccessControlvariants_getattr_and_getitem_. This can lead to critical information disclosure.The
AccessControlpackage already guards against direct access to the formatting functions on string instances, but these mitigations did not cover subclasses ofstr.Affected are all users who allow untrusted users to create AccessControl controlled Python code and execute it.
Patches
A fix was published with version 7.4.
Workarounds
There is no workaround.
- References
-
- https://github.com/zopefoundation/AccessControl/security/advisories/GHSA-pq59-9fq7-m886
- https://nvd.nist.gov/vuln/detail/CVE-2026-77401
- https://github.com/zopefoundation/AccessControl/commit/f980450eea416718be62847f34dfd51822938e43
- https://github.com/zopefoundation/AccessControl
- https://github.com/zopefoundation/AccessControl/releases/tag/7.4
- https://pypi.org/project/accesscontrol
- https://github.com/advisories/GHSA-pq59-9fq7-m886
Affected packages
PyPI / accesscontrol
Package
- Name
- accesscontrol
- View open source insights on deps.dev
- Purl
- pkg:pypi/accesscontrol
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0 Unknown introduced version / All previous versions are affectedFixed7.4
Affected versions
2.*
2.13.0
2.13.1
2.13.2
2.13.3
2.13.4
2.13.5
2.13.6
2.13.7
2.13.8
2.13.9
2.13.10
2.13.11
2.13.12
2.13.13
2.13.14
2.13.15
2.13.16
3.*
3.0
3.0.1
3.0.2
3.0.3
3.0.4
3.0.5
3.0.6
3.0.7
3.0.8
3.0.9
3.0.10
3.0.11
3.0.12
3.0.13
3.0.14
4.*
4.0a1
4.0a2
4.0a3
4.0a4
4.0a5
4.0a6
4.0a7
4.0b1
4.0b2
4.0b3
4.0b4
4.0b5
4.0b6
4.0b7
4.0
4.1
4.2
4.3
4.4
5.*
5.0
5.1
5.2
5.3
5.3.1
5.4
5.5
5.6
5.7
6.*
6.0
6.1
6.2
6.3
7.*
7.0
7.1
7.2
7.3