CVE-2018-12437: Libtom Libtomcrypt

Medium severity, CVSS 4.9. EPSS: 0.5% chance of exploitation in the next 30 days.

LibTomCrypt through 1.18.1 allows a memory-cache side-channel attack on ECDSA signatures, aka the Return Of the Hidden Number Problem or ROHNP. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.

Affected products

• Libtom Libtomcrypt: up to and including 1.18.1
• Trustedfirmware Op-Tee: up to and including 3.5.0

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