CVE-2026-54616: CWE-125: Out-of-bounds Read in M2Team NanaZip
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.
CVSS v3.1
Score 7.1high
Affected software
M2Team
NanaZip
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
NanaZip versions before 6.0.1698.0 contain an out-of-bounds read vulnerability (CWE-125) in the Lz4Decode function within NanaZip.Core/SevenZip/CPP/7zip/Archive/SquashfsHandler.cpp. The function incorrectly treats only zero return values from LZ4_decompress_safe as errors, ignoring negative error codes. These negative values are cast to unsigned types and truncated, causing the _cachedUnpackBlockSize to be inflated. During fragment extraction, an attacker-controlled inode Offset can exploit this to cause memcpy to read beyond the allocated _cachedBlock heap buffer, potentially exposing adjacent heap memory or causing a crash. The vulnerability is fixed in stable version 6.0.1698.0 and preview version 6.5.1742.0.
Potential Impact
An attacker can craft malformed input to trigger an out-of-bounds read, leading to potential exposure of adjacent heap memory contents in extracted files or causing application crashes. The vulnerability does not allow code execution or integrity modification but can result in information disclosure and denial of service.
Mitigation Recommendations
This vulnerability is fixed in NanaZip stable version 6.0.1698.0 and preview version 6.5.1742.0. Users should upgrade to these versions or later to remediate the issue. No other mitigation or workaround is indicated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- GitHub_M
- Date Reserved
- 2026-06-15T20:07:02.184Z
- Cvss Version
- 3.1
- State
- PUBLISHED
Threat ID: 6a8729e3acd9273b49d93230
Added to database: 08/20/2026, 16:22:59 UTC
Last enriched: 08/20/2026, 16:37:11 UTC
Last updated: 10/04/2026, 18:53:17 UTC
Views: 77
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