CVE-2018-12437
Publication date 15 June 2018
Last updated 25 August 2025
Ubuntu priority
Description
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.
From the Ubuntu Security Team
It was discovered that LibTomCrypt incorrectly handled ECDSA signatures. A local attacker could possibly use this issue to obtain sensitive information.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| libtomcrypt | 18.04 LTS bionic |
Fixed 1.18.1-1ubuntu0.1
|
| 16.04 LTS xenial |
Fixed 1.17-7ubuntu0.1
|
|
| 14.04 LTS trusty |
Fixed 1.17-5ubuntu0.1
|
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score |
4.9 · Medium
|
| Attack vector | Physical |
| Attack complexity | High |
| Privileges required | None |
| User interaction | None |
| Scope | Changed |
| Confidentiality | High |
| Integrity impact | None |
| Availability impact | None |
| Vector | CVSS:3.1/AV:P/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N |