CVE-2018-14779 Information

Description

A buffer overflow 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_transfer_data(): highlight c if(*out_len + recv_len - 2 max_out) fprintf(stderr \Output buffer to small wanted to write lu max was lu.\ *out_len + recv_len - 2 max_out); if(out_data) memcpy(out_data data recv_len - 2); out_data += recv_len - 2; *out_len += recv_len - 2; endhighlight – it is clearly checked whether the buffer is big enough to hold the data copied using memcpy() but no error handling happens to avoid the memcpy() in such cases. This code path can be triggered with malicious data coming from a smartcard.

CVSS Vector

CVSS:3.0/AV:P/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Reference

http://www.openwall.com/lists/oss-security/2018/08/14/2 https://usn.ubuntu.com/4276-1/ https://www.x41-dsec.de/lab/advisories/x41-2018-001-Yubico-Piv/ https://www.yubico.com/support/security-advisories/ysa-2018-03/

Attack Complexity

LOW

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

6.8