CVE-2026-55783 (GCVE-0-2026-55783)
Vulnerability from cvelistv5 – Published: 2026-07-10 16:48 – Updated: 2026-07-10 18:38
VLAI
EPSS
VEX
Title
NanaZip: NULL pointer dereference in Extract() of all seven NanaZip custom archive handlers when extracting/testing the whole archive
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-10 18:38 UTC
CWE
- CWE-476 - NULL Pointer Dereference
Assigner
References
3 references
| URL | Tags |
|---|---|
| https://github.com/M2Team/NanaZip/security/adviso… | x_refsource_CONFIRM |
| https://github.com/M2Team/NanaZip/commit/5d74d90b… | x_refsource_MISC |
| https://github.com/M2Team/NanaZip/releases/tag/6.… | x_refsource_MISC |
Impacted products
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