Hello,
this concerns key_method 1. I know it's deprecated, but reporting it
just in case people still use it..
So key_method_1_read() calls read_key() which doesn't perform adequate
bounds checks. cipher_length and hmac_length are specified by the
peer:
1643 uint8_t cipher_length;
1644 uint8_t hmac_length;
1645
1646 CLEAR(*key);
1647 if (!buf_read(buf, &cipher_length, 1))
1648 {
1649 goto read_err;
1650 }
1651 if (!buf_read(buf, &hmac_length, 1))
1652 {
1653 goto read_err;
1654 }
And this many bytes of data are then read into key->cipher and key->hmac:
1656 if (!buf_read(buf, key->cipher, cipher_length))
1657 {
1658 goto read_err;
1659 }
1660 if (!buf_read(buf, key->hmac, hmac_length))
1661 {
1662 goto read_err;
1663 }
key->hmac is only 64 bytes. So it's trivial to overflow key->hmac.
Guido
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