PECL in the download utility class in the Installer in PEAR Base System v1.10.1 does not validate file types and filenames after a redirect, which allows remote HTTP servers to overwrite files via crafted responses, as demonstrated by a .htaccess overwrite.
The PEAR_REST class in REST.php in PEAR in PHP through 5.6.0 allows local users to write to arbitrary files via a symlink attack on a (1) rest.cachefile or (2) rest.cacheid file in /tmp/pear/cache/, related to the retrieveCacheFirst and useLocalCache functions.