CVE-2026-55780CWE-248CWE-400

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

Low · published July 10, 2026

CVSS v4.0
2.4
EPSS
0%
Percentile
35.6
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
2.4 · LOW
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
EPSS
0.00424 · 35.6th percentile
Weaknesses
CWE-248 · Uncaught Exception; CWE-400 · Uncontrolled Resource Consumption
Published
2026-07-10T16:49Z
EPSS history
Timeline
  • 10 JUL 16:49Z
    NanaZip: Uncaught exception / unbounded allocation in NanaZip .NET single-file Extract() via unvalidated entry Size
    cvelistv5