CVE-2026-77401

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.

CVSS v3 6.8 MEDIUM

6.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required HIGH

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/zopefoundation/AccessControl/commit/f980450eea416718be62847f34dfd51822938e43
https://github.com/zopefoundation/AccessControl/releases/tag/7.4
https://github.com/zopefoundation/AccessControl/security/advisories/GHSA-pq59-9fq7-m886

Configurations

No configuration.

History

16 Sep 2026, 15:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-16 15:17

Updated : 2026-09-16 19:17

NVD link : CVE-2026-77401

Mitre link : CVE-2026-77401

CVE.ORG link : CVE-2026-77401

JSON object : View

Products Affected

No product.

CWE

CWE-693

Protection Mechanism Failure

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