Description
NanaZip is the 7-Zip derivative intended for the modern Windows experience. From version 1.0.88.0 until stable version 6.0.1698.0 and preview version 6.5.1742.0, the Lz4Decode function in NanaZip.Core/SevenZip/CPP/7zip/Archive/SquashfsHandler.cpp rejects only a zero return from LZ4_decompress_safe even though malformed input produces a negative error value. The negative int is converted to the unsigned SizeT destLen and then truncated into outBufWasWrittenSize, causing ReadBlock to trust an attacker-inflated _cachedUnpackBlockSize. During fragment extraction, an attacker-controlled inode Offset can make memcpy read beyond the _cachedBlock heap allocation and place adjacent heap contents in the extracted file, or crash the process. This issue is fixed in stable version 6.0.1698.0 and preview version 6.5.1742.0.
References6
- github.com/M2Team/NanaZip/commit/733e8570d2ba96c3e52aab44f5fd88…
- github.com/M2Team/NanaZip/commit/ce0322a1932e16a53e4a13e48bc618…
- github.com/M2Team/NanaZip/releases/tag/6.0.1698.0
- github.com/M2Team/NanaZip/releases/tag/6.5.1742.0
- github.com/M2Team/NanaZip/security/advisories/GHSA-95x5-qvvm-hm…
- github.com/M2Team/NanaZip/security/advisories/GHSA-95x5-qvvm-hm…
Metrics
- CVSS 3.1
-
7.1
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:L - EPSS — exploit probability
- 0% percentile: 39 · as of 10 November 2026
- CWE
- CWE-125
Could this be exploited in your environment?
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