CVE-2018-12439

MatrixSSL through 3.9.5 Open 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.

Published: 2018-06-15 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-12439 is rated Low Risk (25.7/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.27%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-12439

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 0.27% +0.22%
2 2025-03-17 0.04% 0.06% +0.01%
3 2023-03-07 — 0.04% —

Full EPSS history (5 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-12439

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
4.7 3.0 MEDIUM
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
 1.0 3.6 [email protected]
1.9 2.0 LOW
AV:L/AC:M/Au:N/C:P/I:N/A:N Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
 3.4 2.9 [email protected]

Weakness enumeration for CVE-2018-12439

OS Trackers for CVE-2018-12439

vendor priority summary link
ubuntu medium CVE-2018-12439 medium priority: Ubuntu including 1 source packages (matrixssl), 7 status rows across 7 suites (artful, bionic, cosmic, disco, trusty, upstream, xenial): DNE 6, needs-triage 1. https://ubuntu.com/security/CVE-2018-12439

Affected software / configurations for CVE-2018-12439

Vendor Product Version Raw CPE
matrixssl matrixssl <= 3.9.5 cpe:2.3:a:matrixssl:matrixssl:*:*:*:*:*:*:*:*

References for CVE-2018-12439

cvelogic Threat Intelligence