An out-of-bounds read issue was discovered in the Yubico-Piv 1.5.0 smartcard driver. The file lib/ykpiv.c contains the following code in the function `_ykpiv_fetch_object()`: {% highlight c %} if(sw == SW_SUCCESS) { size_t outlen; int offs = _ykpiv_get_length(data + 1, &outlen); if(offs == 0) { return YKPIV_SIZE_ERROR; } memmove(data, data + 1 + offs, outlen); *len = outlen; return YKPIV_OK; } else { return YKPIV_GENERIC_ERROR; } {% endhighlight %} -- in the end, a `memmove()` occurs with a length retrieved from APDU data. This length is not checked for whether it is outside of the APDU data retrieved. Therefore the `memmove()` could copy bytes behind the allocated data buffer into this buffer.
The product reads data past the end, or before the beginning, of the intended buffer.
| Link | Tags |
|---|---|
| https://www.yubico.com/support/security-advisories/ysa-2018-03/ | vendor advisory |
| https://www.x41-dsec.de/lab/advisories/x41-2018-001-Yubico-Piv/ | third party advisory |
| http://www.openwall.com/lists/oss-security/2018/08/14/2 | third party advisory mailing list |
| https://usn.ubuntu.com/4276-1/ | vendor advisory |