When parsing untrusted rulex expressions, rulex may panic, possibly enabling a Denial of Service attack. This happens when the expression contains a multi- byte UTF-8 code point in a string literal or after a backslash, because rulex tries to slice into the code point and panics as a result.
The flaw was corrected in commits fac6d58b25 and 330b3534e7 by using
len_utf8() to derive character width in bytes instead of assuming ASCII
encoding of 1 byte per char.
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    "license": "CC0-1.0"
}