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CVE-2026-77401 (GCVE-0-2026-77401)

Vulnerability from cvelistv5 – Published: 2026-09-16 14:28 – Updated: 2026-09-16 18:35
VLAI
Title
Zope AccessControl: Information disclosure through Python string `format` and `format_map` functions
Summary
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.
Severity
6.8 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-16 18:18 UTC
CWE
  • CWE-693 - Protection Mechanism Failure
Assigner
References
Impacted products
Vendor Product Version CPE status
zopefoundation AccessControl Affected: < 7.4
guessed Create a notification for this product.
Show details on NVD website
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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