py7zr vulnerabilities
3 known CVE vulnerabilities in py7zr, translated and rated.
- CVE-2026-55206High
The py7zr library prior to version 1.1.3 contains a denial-of-service vulnerability causing excessive CPU consumption during SevenZipFile initialization. The PackInfo._read() function in archiveinfo.py uses an O(n^2) cumulative sum pattern for attacker-controlled numstreams values parsed from archive headers, allowing a crafted .7z archive to trigger CPU exhaustion.
- CVE-2026-55195High
The py7zr library before version 1.1.3 does not track the total decompressed size, allowing a decompression bomb attack. A crafted .7z file (e.g., 15.6 KB) can expand to 100 MB, exhausting disk space or memory.
- CVE-2026-23879High
The py7zr library, used for compressing and decompressing 7zip archives, contains an arbitrary file write vulnerability in versions 1.1.2 and below. This allows attackers to create malicious archives that can restore symbolic links to arbitrary directories in the file system.