CVE-2026-44215
MediumCVSS 4.4Exploitation Probability (EPSS)
Low risk20th percentile - higher than 20% of all known CVEs
Summary
In NanaZip from 5.0.1252.0 to before 6.0.1698.0, a one-byte heap out-of-bounds null write exists in the UFS/UFS2 filesystem image parser. The vulnerability is triggered when opening a crafted UFS filesystem image, with the attacker controlling the write offset within a ~254-byte window past the heap allocation boundary.
Risk Assessment
Opening a malicious UFS image may lead to memory corruption and potentially application crash or code execution. The risk affects users opening untrusted archives.
Recommendation
Update NanaZip to version 6.0.1698.0 or later. Avoid opening UFS images from untrusted sources until updated.
Other vulnerabilities in NanaZip
See all- CVE-2026-54616High
NanaZip from version 1.0.88.0 until stable 6.0.1698.0 and preview 6.5.1742.0 has a vulnerability in the Lz4Decode function that rejects only a zero return from LZ4_decompress_safe, while malformed input produces a negative error value. The negative int is converted to unsigned SizeT, leading to out-of-bounds read and potential data leak or crash.
- CVE-2026-55783Low
A vulnerability in NanaZip (a 7-Zip fork for Windows) prior to version 6.5.1749.0 causes a process crash when testing or extracting WebAssembly, ElectronAsar, Zealfs, Romfs, Ufs, Littlefs, and DotNetSingleFile archives. The issue stems from unconditionally dereferencing the caller-supplied Indices pointer, which can be NULL when the archive engine signals extraction of all items.
- CVE-2026-55782Low
NanaZip prior to version 6.5.1749.0 has a vulnerability in its WebAssembly archive handler where an attacker can control buffer allocation sizes. By crafting a file with manipulated NameSize and Information.Size fields, multi-gigabyte memory allocations can be forced, leading to memory exhaustion or process termination.
- CVE-2026-55781Low
A vulnerability in NanaZip (a 7-Zip fork for Windows) prior to version 6.5.1749.0 allows an attacker to cause memory exhaustion via a crafted UFS/FFS image. Missing validation of the fragment size (fs_fsize) lets a tiny image force multi-gigabyte allocations during open or extraction.
- CVE-2026-55780Low
A vulnerability in NanaZip (a 7-Zip fork for Windows) prior to version 6.5.1749.0 allows process crashes via a crafted .NET single-file bundle. The issue stems from missing validation of the extraction buffer size against the actual file size, potentially leading to std::bad_alloc or std::length_error exceptions.
- CVE-2026-42446Medium
A stack-based out-of-bounds read exists in the ZealFS filesystem image parser in NanaZip from 5.0.1252.0 to before 6.0.1698.0. Triggered by opening a crafted ZealFS v1 image, an attacker-controlled BitmapSize field drives an unbounded loop reading past the stack-allocated ZEALFS_V1_HEADER.
- CVE-2026-42445Low
An uncontrolled recursion vulnerability exists in the UFS/UFS2 filesystem image parser in NanaZip from 5.0.1252.0 to before 6.0.1698.0. The GetAllPaths function recurses into subdirectories without a depth limit, causing stack exhaustion and a crash when opening a crafted image.
- CVE-2026-42444Low
A denial-of-service vulnerability exists in the littlefs filesystem image parser in NanaZip from 5.0.1252.0 to before 6.0.1698.0. The Open method reads BlockCount from the attacker-controlled superblock without validation, causing billions of heap allocations and memory exhaustion.
- CVE-2026-42443Low
NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, an integer divide-by-zero exists in the UFS/UFS2 filesystem image parser. The vulnerability is triggered when opening a crafted UFS image where the superblock field fs_ipg (inodes per cylinder group) is set to zero; the parser uses this attacker-controlled value as a divisor without validation, causing an immediate hardware trap and process crash. This vulnerability is fixed in 6.0.1698.0.
- CVE-2026-42442Low
A null-pointer dereference exists in the UFS/UFS2 filesystem image parser in NanaZip from 5.0.1252.0 to before 6.0.1698.0. When the root inode is a symlink instead of a directory, the parser causes a null-pointer dereference.
Original NVD description (English source)
NanaZip is an open source file archive. From 5.0.1252.0 to before 6.0.1698.0, a one-byte heap out-of-bounds null write exists in the UFS/UFS2 filesystem image parser in NanaZip. The vulnerability is triggered when opening a crafted UFS filesystem image. The attacker controls the byte offset of the write within a ~254-byte window past the heap allocation boundary. This vulnerability is fixed in 6.0.1698.0.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

