CVE-2018-14779: Yubico Piv Manager

Medium severity, CVSS 6.8. EPSS: 0.5% chance of exploitation in the next 30 days.

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.

Affected products

• Yubico Piv Manager: before 1.4.2 (fixed in 1.4.2); version 1.4.2 only; version 1.4.2b only; version 1.4.2c only; version 1.4.2d only; version 1.4.2e only; …
• Yubico Piv Tool: before 1.6.0 (fixed in 1.6.0)
• Yubico Smart Card Minidriver: up to and including 3.7.3.160

Published 2018-08-15. Last modified 2026-06-17.