Deserialization of Untrusted Data in Archive_Tar - CVE-2018-1000888
Published: January 17, 2019 / Updated: June 17, 2021
Vulnerability identifier: #VU17066
CSH Severity: Medium
CVSS v4 BT: 0 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/U:Green]
CVE-ID: CVE-2018-1000888
CWE-ID: CWE-502
Exploitation vector: Remote access
Exploit availability:
Public exploit is available
Vulnerability details
The vulnerability allows a remote attacker to execute arbitrary code on the target system.
The vulnerability exists due to insecure input validation when processing serialized data within tar files. A remote attacker can create a tar file with `phar://[path_to_malicious_phar_file]` as path and execute arbitrary code on the target system.
Affected software
Archive_Tar
Gentoo Linux
php-pear (Debian package)
drupal7 (Alpine package)
Gentoo Linux
php-pear (Debian package)
drupal7 (Alpine package)
How to mitigate CVE-2018-1000888
Install updates from vendor's website.
Archive_Tar - update to 1.4.4
php-pear (Debian package) - update to 1:1.10.1+submodules+notgz-9+deb9u1
drupal7 (Alpine package) - update to 7.62-r0
php-pear (Debian package) - update to 1:1.10.1+submodules+notgz-9+deb9u1
drupal7 (Alpine package) - update to 7.62-r0
External References
- https://blog.ripstech.com/2018/new-php-exploitation-technique/
- https://cdn2.hubspot.net/hubfs/3853213/us-18-Thomas-It%27s-A-PHP-Unserialization-Vulnerability-Jim-But-Not-As-We-....pdf
- https://pear.php.net/bugs/bug.php?id=23782
- https://pear.php.net/package/Archive_Tar/download/
- https://usn.ubuntu.com/3857-1/
- https://www.exploit-db.com/exploits/46108/