CVE-2026-55780

LOW

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

Title source: cna
STIX 2.1

Description

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.

References (3)

Core 3

Scores

CVSS v4 2.4
EPSS 0.0011
EPSS Percentile 1.6%
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation poc
Automatable no
Technical Impact partial

Details

CWE
CWE-248 CWE-400
Status published
Products (1)
M2Team/NanaZip < 6.5.1749.0
Published Jul 10, 2026
Tracked Since Jul 10, 2026