PHP before 4.4.3 and 5.x before 5.1.4 does not limit the character set of the session identifier (PHPSESSID) for third party session handlers, which might make it easier for remote attackers to exploit other vulnerabilities by inserting PHP code into the PHPSESSID, which is stored in the session file. NOTE: it could be argued that this not a vulnerability in PHP itself, rather a design limitation that enables certain attacks against session handlers that do not account for this limitation.

An issue was discovered in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1. Invalid input to the function xmlrpc_decode() can lead to an invalid memory access (heap out of bounds read or read after free). This is related to xml_elem_parse_buf in ext/xmlrpc/libxmlrpc/xml_element.c.

PHP remote file inclusion vulnerability in includes/common.php in the ErrorDocs 1.0.0 and earlier module for mxBB (mx_errordocs) allows remote attackers to execute arbitrary PHP code via a URL in the module_root_path parameter.

The zend_alter_ini_entry function in PHP before 5.2.4 does not properly handle an interruption to the flow of execution triggered by a memory_limit violation, which has unknown impact and attack vectors.

Buffer overflow in openlog function for PHP 4.3.1 on Windows operating system, and possibly other OSes, allows remote attackers to cause a crash and possibly execute arbitrary code via a long filename argument.

Unknown vulnerability in CGI module for PHP 4.3.0 allows attackers to access arbitrary files as the PHP user, and possibly execute PHP code, by bypassing the CGI force redirect settings (cgi.force_redirect or --enable-force-cgi-redirect).

The php_check_safe_mode_include_dir function in fopen_wrappers.c of PHP 4.3.x returns a success value (0) when the safe_mode_include_dir variable is not specified in configuration, which differs from the previous failure value and may allow remote attackers to exploit file include vulnerabilities in PHP applications.

Unspecified vulnerability in the chunk_split function in PHP before 5.2.4 has unknown impact and attack vectors, related to an incorrect size calculation.

Heap-based buffer overflow in the wordwrap function in PHP after 4.1.2 and before 4.3.0 may allow attackers to cause a denial of service or execute arbitrary code.

Argument injection vulnerability in the mail function for PHP 4.x to 4.2.2 may allow attackers to bypass safe mode restrictions and modify command line arguments to the MTA (e.g. sendmail) in the 5th argument to mail(), altering MTA behavior and possibly executing commands.

Safe Mode feature (safe_mode) in PHP 3.0 through 4.1.0 allows attackers with access to the MySQL database to bypass Safe Mode access restrictions and read arbitrary files using "LOAD DATA INFILE LOCAL" SQL statements.

Buffer overflows in (1) php_mime_split in PHP 4.1.0, 4.1.1, and 4.0.6 and earlier, and (2) php3_mime_split in PHP 3.0.x allows remote attackers to execute arbitrary code via a multipart/form-data HTTP POST request when file_uploads is enabled.

PHP 4.0.5 through 4.1.0 in safe mode does not properly cleanse the 5th parameter to the mail() function, which allows local users and possibly remote attackers to execute arbitrary commands via shell metacharacters.

The proxy server feature in go-pear.php in PHP PEAR 0.2.2, as used in Apache2Triad, allows remote attackers to execute arbitrary PHP code by redirecting go-pear.php to a malicious proxy server that provides a modified version of Tar.php with a malicious extractModify function.

PHP treats unknown methods such as "PoSt" as a GET request, which could allow attackers to intended access restrictions if PHP is running on a server that passes on all methods, such as Apache httpd 2.0, as demonstrated using a Limit directive. NOTE: this issue has been disputed by the Apache security team, saying "It is by design that PHP allows scripts to process any request method. A script which does not explicitly verify the request method will hence be processed as normal for arbitrary methods. It is therefore expected behaviour that one cannot implement per-method access control using the Apache configuration alone, which is the assumption made in this report.

Integer overflow in the zip_read_entry function in PHP 4 before 4.4.5 allows remote attackers to execute arbitrary code via a ZIP archive that contains an entry with a length value of 0xffffffff, which is incremented before use in an emalloc call, triggering a heap overflow.

Integer signedness error in emalloc() function for PHP before 4.3.2 allow remote attackers to cause a denial of service (memory consumption) and possibly execute arbitrary code via negative arguments to functions such as (1) socket_recv, (2) socket_recvfrom, and possibly other functions.

Buffer overflow in PHP cgi program, php.cgi allows shell access.

PHP-Memcached v2.2.0 and below contains an improper NULL termination which allows attackers to execute CLRF injection. Note: Third parties have disputed this as not affecting PHP-Memcached directly.

Unspecified vulnerability in the imagecolortransparent function in PHP before 5.2.11 has unknown impact and attack vectors related to an incorrect "sanity check for the color index."

ext/soap/soap.c in PHP before 5.3.22 and 5.4.x before 5.4.13 does not validate the relationship between the soap.wsdl_cache_dir directive and the open_basedir directive, which allows remote attackers to bypass intended access restrictions by triggering the creation of cached SOAP WSDL files in an arbitrary directory.

The secureCompare method in lib/SimpleSAML/Utils/Crypto.php in SimpleSAMLphp 1.14.13 and earlier, when used with PHP before 5.6, allows attackers to conduct session fixation attacks or possibly bypass authentication by leveraging missing character conversions before an XOR operation.

The finish_nested_data function in ext/standard/var_unserializer.re in PHP before 5.6.31, 7.0.x before 7.0.21, and 7.1.x before 7.1.7 is prone to a buffer over-read while unserializing untrusted data. Exploitation of this issue can have an unspecified impact on the integrity of PHP.

ext/standard/var_unserializer.re in PHP 7.0.x through 7.0.22 and 7.1.x through 7.1.8 is prone to a heap use after free while unserializing untrusted data, related to improper use of the hash API for key deletion in a situation with an invalid array size. Exploitation of this issue can have an unspecified impact on the integrity of PHP.

PHP through 5.6.27 and 7.x through 7.0.12 mishandles property modification during __wakeup processing, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted serialized data, as demonstrated by Exception::__toString with DateInterval::__wakeup.

Use-after-free vulnerability in the substr_replace function in PHP 5.3.6 and earlier allows context-dependent attackers to cause a denial of service (memory corruption) or possibly have unspecified other impact by using the same variable for multiple arguments.

The php_wddx_process_data function in ext/wddx/wddx.c in PHP before 5.6.25 and 7.x before 7.0.10 allows remote attackers to cause a denial of service (segmentation fault) or possibly have unspecified other impact via an invalid ISO 8601 time value, as demonstrated by a wddx_deserialize call that mishandles a dateTime element in a wddxPacket XML document.

The qstr method in the PDO driver in the ADOdb Library for PHP before 5.x before 5.20.7 might allow remote attackers to conduct SQL injection attacks via vectors related to incorrect quoting.

ext/spl/spl_array.c in PHP before 5.6.26 and 7.x before 7.0.11 proceeds with SplArray unserialization without validating a return value and data type, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted serialized data.

The imagegammacorrect function in ext/gd/gd.c in PHP before 5.6.25 and 7.x before 7.0.10 does not properly validate gamma values, which allows remote attackers to cause a denial of service (out-of-bounds write) or possibly have unspecified other impact by providing different signs for the second and third arguments.

Use-after-free vulnerability in the wddx_stack_destroy function in ext/wddx/wddx.c in PHP before 5.6.26 and 7.x before 7.0.11 allows remote attackers to cause a denial of service or possibly have unspecified other impact via a wddxPacket XML document that lacks an end-tag for a recordset field element, leading to mishandling in a wddx_deserialize call.

A type confusion vulnerability in the merge_param() function of php_http_params.c in PHP's pecl-http extension 3.1.0beta2 (PHP 7) and earlier as well as 2.6.0beta2 (PHP 5) and earlier allows attackers to crash PHP and possibly execute arbitrary code via crafted HTTP requests.

The imagetruecolortopalette function in ext/gd/gd.c in PHP before 5.6.25 and 7.x before 7.0.10 does not properly validate the number of colors, which allows remote attackers to cause a denial of service (select_colors allocation error and out-of-bounds write) or possibly have unspecified other impact via a large value in the third argument.

ext/standard/var_unserializer.c in PHP before 5.6.25 and 7.x before 7.0.10 mishandles certain invalid objects, which allows remote attackers to cause a denial of service or possibly have unspecified other impact via crafted serialized data that leads to a (1) __destruct call or (2) magic method call.

Integer overflow in the gdImageWebpCtx function in gd_webp.c in the GD Graphics Library (aka libgd) through 2.2.3, as used in PHP through 7.0.11, allows remote attackers to cause a denial of service (heap-based buffer overflow) or possibly have unspecified other impact via crafted imagewebp and imagedestroy calls.

php_zip.c in the zip extension in PHP before 5.5.37, 5.6.x before 5.6.23, and 7.x before 7.0.8 improperly interacts with the unserialize implementation and garbage collection, which allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free and application crash) via crafted serialized data containing a ZipArchive object.

ext/session/session.c in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9 does not properly maintain a certain hash data structure, which allows remote attackers to cause a denial of service (use-after-free) or possibly have unspecified other impact via vectors related to session deserialization.

ext/snmp/snmp.c in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9 improperly interacts with the unserialize implementation and garbage collection, which allows remote attackers to cause a denial of service (use-after-free and application crash) or possibly have unspecified other impact via crafted serialized data, a related issue to CVE-2016-5773.

Multiple integer overflows in mcrypt.c in the mcrypt extension in PHP before 5.5.37, 5.6.x before 5.6.23, and 7.x before 7.0.8 allow remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted length value, related to the (1) mcrypt_generic and (2) mdecrypt_generic functions.

spl_array.c in the SPL extension in PHP before 5.5.37 and 5.6.x before 5.6.23 improperly interacts with the unserialize implementation and garbage collection, which allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free and application crash) via crafted serialized data.

An issue was discovered in the EXIF component in PHP before 7.1.27, 7.2.x before 7.2.16, and 7.3.x before 7.3.3. There is an uninitialized read in exif_process_IFD_in_TIFF.

The locale_accept_from_http function in ext/intl/locale/locale_methods.c in PHP before 5.5.38, 5.6.x before 5.6.24, and 7.x before 7.0.9 does not properly restrict calls to the ICU uloc_acceptLanguageFromHTTP function, which allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a call with a long argument.

Double free vulnerability in the php_wddx_process_data function in wddx.c in the WDDX extension in PHP before 5.5.37, 5.6.x before 5.6.23, and 7.x before 7.0.8 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via crafted XML data that is mishandled in a wddx_deserialize call.

Integer overflow in the SplFileObject::fread function in spl_directory.c in the SPL extension in PHP before 5.5.37 and 5.6.x before 5.6.23 allows remote attackers to cause a denial of service or possibly have unspecified other impact via a large integer argument, a related issue to CVE-2016-5096.

Double free vulnerability in the _php_mb_regex_ereg_replace_exec function in php_mbregex.c in the mbstring extension in PHP before 5.5.37, 5.6.x before 5.6.23, and 7.x before 7.0.8 allows remote attackers to execute arbitrary code or cause a denial of service (application crash) by leveraging a callback exception.

The grapheme_strpos function in ext/intl/grapheme/grapheme_string.c in PHP before 5.5.35, 5.6.x before 5.6.21, and 7.x before 7.0.6 allows remote attackers to cause a denial of service (out-of-bounds read) or possibly have unspecified other impact via a negative offset.

An issue was discovered in PHP before 5.6.40, 7.x before 7.1.26, 7.2.x before 7.2.14, and 7.3.x before 7.3.1. A number of heap-based buffer over-read instances are present in mbstring regular expression functions when supplied with invalid multibyte data. These occur in ext/mbstring/oniguruma/regcomp.c, ext/mbstring/oniguruma/regexec.c, ext/mbstring/oniguruma/regparse.c, ext/mbstring/oniguruma/enc/unicode.c, and ext/mbstring/oniguruma/src/utf32_be.c when a multibyte regular expression pattern contains invalid multibyte sequences.