The PHP development team has announced the immediate availability of PHP 5.3.1. This release focuses on improving the stability of the PHP 5.3.x branch with over 100 bug fixes, some of which are security related. All users are encouraged to upgrade to this release.

Security Enhancements and Fixes in PHP 5.3.1:
- Added "max_file_uploads" INI directive, which can be set to limit the
number of file uploads per-request to 20 by default, to prevent
possible DOS via temporary file exhaustion. (Ilia)
- Added missing sanity checks around exif processing. (CVE-2009-3292, Ilia)
- Fixed a safe_mode bypass in tempnam() identified by Grzegorz Stachowiak.
(CVE-2009-3557, Rasmus)
- Fixed a open_basedir bypass in posix_mkfifo() identified by Grzegorz
Stachowiak. (CVE-2009-3558, Rasmus)
- Fixed bug #50063 (safe_mode_include_dir fails). (CVE-2009-3559,
Johannes, christian at elmerot dot se)
- Fixed bug #44683 (popen crashes when an invalid mode is passed).
(CVE-2009-3294, Pierre)

Key Enhancements in PHP 5.3.1 include:
- Fixed crash in com_print_typeinfo when an invalid typelib is given. (Pierre)
- Fixed crash in SQLiteDatabase::ArrayQuery() and SQLiteDatabase::SingleQuery()
when calling using Reflection. (Felipe)
- Fixed crash when instantiating PDORow and PDOStatement through Reflection.
(Felipe)
- Fixed bug #49910 (no support for ././@LongLink for long filenames in phar
tar support). (Greg)
- Fixed bug #49908 (throwing exception in __autoload crashes when interface
is not defined). (Felipe)
- Around 100 other bug fixes

For users upgrading from PHP 5.2 there is a migration guide available on , detailing the changes between those releases and PHP 5.3.

For a full list of changes in PHP 5.3.1, see the ChangeLog at .

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