Out-of-bounds Write (CWE-787) in the PEA archive extraction routine (pea.pas, unpeaprocedure) of the first-party pea component in PeaZip 11.2.0 and earlier allows an attacker who convinces a victim to open or extract a crafted .pea archive to execute arbitrary code as the user running PeaZip. While decompressing a PCOMPRESS1 stream, the 32-bit compressed-block-size field of the first block (compsize) is read directly from the archive and used without validation as the length of a blockread into the fixed-size global buffers wbuf1/wbuf2 (1,114,112 bytes) and as the bound of the subsequent copy loop. The existing check "compsize > WBUFSIZE" is applied only to the size of each following block, so the first block escapes it; the same unvalidated value is also used to index wbuf1[compsize], an out-of-bounds read at an attacker-chosen offset. The copy loop additionally copies the requested length instead of the number of bytes actually read, and terminates on equality rather than on an upper bound. Because the project is built without range checking and no archive password, integrity tag or non-default configuration is required, the overflow overwrites adjacent global data; code execution was demonstrated by two independent researchers against the official Linux x86-64 and Windows x64 builds, and the denial-of-service and memory-corruption primitive is cross-platform (Windows, macOS, Linux, BSD).

In PeaZip through 10.4.0, there is a Mark-of-the-Web Bypass Vulnerability. This vulnerability allows attackers to bypass the Mark-of-the-Web protection mechanism on affected installations of PeaZip. User interaction is required to exploit this vulnerability in that the target must visit a malicious page or open a malicious file. The specific flaw exists within the handling of archived files. When extracting files from a crafted archive that bears the Mark-of-the-Web, PeaZip does not propagate the Mark-of-the-Web to the extracted files. An attacker can leverage this vulnerability to execute arbitrary code in the context of the current user. NOTE: this is disputed because Mark-of-the-Web propagation can increase risk via security-warning habituation, and because the intended control sphere for file-origin metadata (e.g., HostUrl in Zone.Identifier) may be narrower than that for reading the file's content.

A vulnerability has been found in PeaZip 9.4.0 and classified as problematic. Affected by this vulnerability is an unknown functionality in the library dragdropfilesdll.dll of the component Library Handler. The manipulation leads to uncontrolled search path. An attack has to be approached locally. Upgrading to version 9.6.0 is able to address this issue. It is recommended to upgrade the affected component. The associated identifier of this vulnerability is VDB-248251. NOTE: Vendor was contacted early, confirmed the existence of the flaw and immediately worked on a patched release.