CVE-2018-1000888

PEAR Archive_Tar version 1.4.3 and earlier contains a CWE-502, CWE-915 vulnerability in the Archive_Tar class. There are several file operations with `$v_header['filename']` as parameter (such as file_exists, is_file, is_dir, etc). When extract is called without a specific prefix path, we can trigger unserialization by crafting a tar file with `phar://[path_to_malicious_phar_file]` as path. Object injection can be used to trigger destruct in the loaded PHP classes, e.g. the Archive_Tar class itself. With Archive_Tar object injection, arbitrary file deletion can occur because `@unlink($this->_temp_tarname)` is called. If another class with useful gadget is loaded, it may possible to cause remote code execution that can result in files being deleted or possibly modified. This vulnerability appears to have been fixed in 1.4.4.

• CWE-502

• https://blog.ripstech.com/2018/new-php-exploitation-technique/Exploit, Third Party Advisory
• https://cdn2.hubspot.net/hubfs/3853213/us-18-Thomas-It%27s-A-PHP-Unserialization-Vulnerability-Jim-But-Not-As-We-....pdfExploit, Technical Description, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2019/02/msg00020.htmlThird Party Advisory
• https://pear.php.net/bugs/bug.php?id=23782Broken Link, Third Party Advisory
• https://pear.php.net/package/Archive_Tar/download/Broken Link, Third Party Advisory
• https://security.gentoo.org/glsa/202006-14
• https://usn.ubuntu.com/3857-1/Third Party Advisory
• https://www.debian.org/security/2019/dsa-4378Third Party Advisory
• https://www.exploit-db.com/exploits/46108/Exploit, Third Party Advisory, VDB Entry
• https://blog.ripstech.com/2018/new-php-exploitation-technique/Exploit, Third Party Advisory
• https://cdn2.hubspot.net/hubfs/3853213/us-18-Thomas-It%27s-A-PHP-Unserialization-Vulnerability-Jim-But-Not-As-We-....pdfExploit, Technical Description, Third Party Advisory
• https://lists.debian.org/debian-lts-announce/2019/02/msg00020.htmlThird Party Advisory
• https://pear.php.net/bugs/bug.php?id=23782Broken Link, Third Party Advisory
• https://pear.php.net/package/Archive_Tar/download/Broken Link, Third Party Advisory
• https://security.gentoo.org/glsa/202006-14
• https://usn.ubuntu.com/3857-1/Third Party Advisory
• https://www.debian.org/security/2019/dsa-4378Third Party Advisory
• https://www.exploit-db.com/exploits/46108/Exploit, Third Party Advisory, VDB Entry

Published

Dec 28, 2018

Last Modified

Jun 17, 2026

Status

Modified