This indicates an attempt to exploit a buffer overflow vulnerability in Apache mod_ssl.
The "ssl_util_uuencode_binary" function in "ssl_util.c" for Apache mod_ssl has a stack-based buffer overflow vulnerability. A remote attacker can execute arbitrary code on a vulnerable system via a client certificate with a long subject DN.
mod_ssl 2.8.16 and prior.
System compromise: remote code execution.
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