PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5.
It was found that the compile_bracket_matchingpath function in pcre_jit_compile.c in PCRE library is vulnerable to an out-of-bounds read.
A remote attacker could possibly cause a Denial of Service condition via a special crafted regular expression.
There is no known workaround at this time.
All PCRE library users should upgrade to the latest version:
# emerge --sync
# emerge --ask --oneshot --verbose ">=dev-libs/libpcre-8.40-r1"