CVE-2026-55780 PUBLISHED

NanaZip: Uncaught exception / unbounded allocation in NanaZip .NET single-file Extract() via unvalidated entry Size

Assigner: GitHub_M
Reserved: 17.06.2026 Published: 10.07.2026 Updated: 10.07.2026

NanaZip is the 7-Zip derivative intended for the modern Windows experience. Prior to 6.5.1749.0, NanaZip's .NET single-file bundle handler in NanaZip.Codecs.Archive.DotNetSingleFile.cpp sizes its extraction buffer from the bundle entry Size field, which is only checked for sign and is not validated against the real file size. A crafted bundle can cause an attacker-chosen allocation inside Extract, where std::bad_alloc or std::length_error can escape across the COM STDMETHODCALLTYPE boundary and crash the process. This issue is fixed in version 6.5.1749.0.

Metrics

CVSS Vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
CVSS Score: 2.4

Product Status

Vendor M2Team
Product NanaZip
Versions
  • Version < 6.5.1749.0 is affected

References

Problem Types

  • CWE-248: Uncaught Exception CWE
  • CWE-400: Uncontrolled Resource Consumption CWE