CVE-2026-55780lowCWE-248CWE-400

CVE-2026-55780: low-severity vulnerability in M2Team NanaZip

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

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28Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 2.4epss 0.6%
from disclosure to weapon38 days
Published on NVDJul 10
1st PoC+38d
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.
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
Affected products
M2Team · NanaZip
⚠ Public resources, to assess the exposure of systems you control or are authorized to test. Test only with authorization.
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