CVE-2026-55783

LOW

NanaZip: NULL pointer dereference in Extract() of all seven NanaZip custom archive handlers when extracting/testing the whole archive

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 seven in-house IInArchive handlers in NanaZip.Codecs unconditionally dereference the caller-supplied Indices array inside Extract when the archive engine signals extract everything by passing Indices as NULL and NumItems as 0xFFFFFFFF. This causes a NULL pointer dereference in the standard Test archive or Extract all code path for WebAssembly, ElectronAsar, Zealfs, Romfs, Ufs, Littlefs, and DotNetSingleFile archives, resulting in a process crash. This issue is fixed in version 6.5.1749.0.

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-476
Status published
Products (1)
M2Team/NanaZip < 6.5.1749.0
Published Jul 10, 2026
Tracked Since Jul 10, 2026