Buffer overflows in PHP before 4.3.3 have unknown impact and unknown attack vectors.

Buffer underflow in the header function in PHP 5.2.0 allows context-dependent attackers to execute arbitrary code by passing an all-whitespace string to this function, which causes it to write '\0' characters in whitespace that precedes the string.

Multiple integer overflows in the chunk_split function in PHP 5 before 5.2.3 and PHP 4 before 4.4.8 allow remote attackers to cause a denial of service (crash) or execute arbitrary code via the (1) chunks, (2) srclen, and (3) chunklen arguments.

PHP 5.2.0 and 4.4 allows local users to bypass safe_mode and open_basedir restrictions via a malicious path and a null byte before a ";" in a session_save_path argument, followed by an allowed path, which causes a parsing inconsistency in which PHP validates the allowed path but sets session.save_path to the malicious path.

Integer overflow in the SdnToJulian function in the Calendar extension in PHP before 5.3.6 allows context-dependent attackers to cause a denial of service (application crash) via a large integer in the first argument to the cal_from_jd function.

PHP before 5.3.7 does not properly implement the error_log function, which allows context-dependent attackers to cause a denial of service (application crash) via unspecified vectors.

Stack overflow in phar with circular symlinks

The (1) strip_tags, (2) setcookie, (3) strtok, (4) wordwrap, (5) str_word_count, and (6) str_pad functions in PHP 5.2 through 5.2.13 and 5.3 through 5.3.2 allow context-dependent attackers to obtain sensitive information (memory contents) by causing a userspace interruption of an internal function, related to the call time pass by reference feature.

Header parser of `http` stream wrapper does not handle folded headers

file before 5.18, as used in the Fileinfo component in PHP before 5.6.0, allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via a zero root_storage value in a CDF file, related to cdf.c and readcdf.c.

Buffer underflow in PHP before 5.2.1 allows attackers to cause a denial of service via unspecified vectors involving the sapi_header_op function.

ext/xml/xml.c in PHP before 5.3.27 does not properly consider parsing depth, which allows remote attackers to cause a denial of service (heap memory corruption) or possibly have unspecified other impact via a crafted document that is processed by the xml_parse_into_struct function.

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.

The exif_process_IFD_in_TIFF function in ext/exif/exif.c in PHP before 5.6.25 and 7.x before 7.0.10 mishandles the case of a thumbnail offset that exceeds the file size, which allows remote attackers to obtain sensitive information from process memory via a crafted TIFF image.

PHP 3 and 4 do not properly cleanse user-injected format strings, which allows remote attackers to execute arbitrary commands by triggering error messages that are improperly written to the error logs.

The readfile function in PHP 4.4.4, 5.1.6, and 5.2.1 allows context-dependent attackers to bypass safe_mode restrictions and read arbitrary files by referring to local files with a certain URL syntax instead of a pathname syntax, as demonstrated by a filename preceded a "php://../../" sequence.

In PHP before 5.6.31, 7.x before 7.0.21, and 7.1.x before 7.1.7, a stack-based buffer overflow in the zend_ini_do_op() function in Zend/zend_ini_parser.c could cause a denial of service or potentially allow executing code. NOTE: this is only relevant for PHP applications that accept untrusted input (instead of the system's php.ini file) for the parse_ini_string or parse_ini_file function, e.g., a web application for syntax validation of php.ini directives.

The __PHP_Incomplete_Class function in ext/standard/incomplete_class.c in PHP before 5.4.40, 5.5.x before 5.5.24, and 5.6.x before 5.6.8 allows remote attackers to cause a denial of service (application crash) or possibly execute arbitrary code via an unexpected data type, related to a "type confusion" issue.

Reference counting in php_request_shutdown causes Use-After-Free

The zend_hash_init function in PHP 5 before 5.2.1 and PHP 4 before 4.4.5, when running on a 64-bit platform, allows context-dependent attackers to cause a denial of service (infinite loop) by unserializing certain integer expressions, which only cause 32-bit arguments to be used after the check for a negative value, as demonstrated by an "a:2147483649:{" argument.