The MITRE CVE dictionary describes this issue as:
PHP 5.2.5 and earlier allows context-dependent attackers to cause a denial of service (application crash) via a long string in (1) the domain parameter to the dgettext function, the message parameter to the (2) dcgettext or (3) gettext function, the msgid1 parameter to the (4) dngettext or (5) ngettext function, or (6) the classname parameter to the stream_wrapper_register function. NOTE: this might not be a vulnerability in most web server environments that support multiple threads, unless this issue can be demonstrated for code execution.
Find out more about CVE-2007-6039 from the
MITRE CVE dictionary dictionary and
NIST NVD.
Statement
Red Hat doesnt consider this a security issue. The arguments to the functions in question should always be under the control of the script author, rather than untrusted script input, so these issues would not be treated as security-sensitive.