There is 1 open security issue in trixie.
1 ignored issue:
- CVE-2026-58052:
7-Zip for Windows through 26.01 fails to preserve the Mark-of-the-Web when extracting a crafted RAR5 archive, because its guard that suppresses an archive-supplied Zone.Identifier stream matches the exact name 'Zone.Identifier' while a RAR5 STM record named ':Zone.Identifier:$DATA' is not matched and NTFS canonicalizes it to the same stream, overwriting the propagated Internet-zone marker with ZoneId=0. A second STM record named '::$DATA' overwrites the extracted file's default data stream, letting an attacker defeat SmartScreen/MotW warnings and spoof file content.
3 issues that should be fixed with the next stable update:
- CVE-2026-14266:
- CVE-2026-48095:
7-Zip is a file archiver with a high compression ratio. Versions 26.00 and prior contain a heap buffer overflow vulnerability caused by an under-allocation in the NTFS compressed stream buffer (GetCuSize shift UB), potentially allowing attackers to cause arbitrary code execution or application crashes. CInStream::GetCuSize() in the NTFS handler computes the compression-unit buffer size as (UInt32)1 << (BlockSizeLog + CompressionUnit), and a crafted image with ClusterSizeLog >= 28 and CompressionUnit == 4 drives the exponent to 32, which is undefined behavior and collapses on x86/x64 so _inBuf is allocated as 1 byte. ReadStream_FALSE then writes up to 256 MB of attacker-controlled data into that 1-byte buffer in 64 KB iterations, and because the CInStream object sits only 304 bytes after _inBuf, its vtable pointer is overwritten and the next dispatched call achieves a vtable hijack. On 32-bit builds the overflow is unconditionally reached; on 64-bit it requires the parallel 8 GB _outBuf allocation to succeed, otherwise failing closed to denial of service. The NTFS handler is enabled by default in stock 7z.dll and, via signature-based fallback matching "NTFS " at offset 3, will open a crafted image regardless of file extension during extraction or testing. Version 26.01 fixes the issue.
- CVE-2026-48112:
7-Zip is a file archiver with a high compression ratio. Versions 9.18 through 26.00 contain a heap out-of-bounds read in 7-Zip Ar handler BSD SYMDEF parser. A 4-byte heap out-of-bounds read exists in the Unix ar archive parser in 7-Zip. When parsing a BSD-style __.SYMDEF symbol table, the ParseLibSymbols function reads a 32-bit namesSize field via Get32 at a position that can equal the buffer size, reading 4 bytes past the end of the heap allocation. This reads uninitialized heap data under the default allocator. Version 26.01 patches the issue.
![[bug history graph]](https://qa.debian.org/data/bts/graphs/7/7zip.png){kind=link}