Shaanan Cohney

A mismatch between encoding lists in Oniguruma and mbfl leads to a NULL pointer dereference, which results in a segmentation fault and denial of service. This occurs when user-controlled input influences the encoding passed to the `mb regex encoding()` function.

The issue is related to the lack of protection for internal data in the Tcl component of the operating system. It can be exploited by a remote attacker to obtain sensitive information by leveraging SSLv2 support.