Perl is vulnerable to a heap buffer overflow when transliterating non-ASCII bytes

A heap buffer overflow vulnerability was discovered in Perl.

Release branches 5.34, 5.36, 5.38 and 5.40 are affected, including development versions from 5.33.1 through 5.41.10.

When there are non-ASCII bytes in the left-hand-side of the tr operator, S_do_trans_invmap can overflow the destination pointer d.

$ perl -e '$_ = "\x{FF}" x 1000000; tr/\xFF/\x{100}/;' Segmentation fault (core dumped)

It is believed that this vulnerability can enable Denial of Service and possibly Code Execution attacks on platforms that lack sufficient defenses.