Security readout for executives and security teams
Plain-English summary
CVE-2018-12439 is a side-channel issue in MatrixSSL through 3.9.5 Open. An attacker with local access, or a co-resident VM on the same physical host, may be able to recover ECDSA signing keys. This is not described as remotely exploitable from the network alone.
Executive priority
Treat this as targeted-risk work, not broad emergency response. Prioritize asset discovery where MatrixSSL is embedded in shared infrastructure or protects high-value ECDSA private keys.
Technical view
The CVE describes ROHNP, a memory-cache side-channel attack against ECDSA signatures in MatrixSSL through 3.9.5 Open. The stated attacker position is local machine access or another virtual machine on the same physical host. No CVSS, CWE, patch version, or vendor mitigation is provided in the supplied sources.
Likely exposure
Exposure is most likely in products, appliances, firmware, or applications embedding MatrixSSL through 3.9.5 Open and using ECDSA keys on shared or locally accessible hosts.
Exploitation context
The source bundle does not show KEV listing or active exploitation. Exploitation requires a local or same-physical-host VM position, making cloud co-tenancy and shared systems more relevant than ordinary remote scanning.
Researcher notes
The supplied record lacks CVSS, CWE, affected CPEs, and explicit fix details. Analysis should stay bounded to MatrixSSL through 3.9.5 Open and the ROHNP cache side-channel prerequisites described in the CVE.
Mitigation direction
- Inventory systems and products that embed MatrixSSL through 3.9.5 Open.
- Check MatrixSSL or product-vendor guidance for fixed versions or supported mitigations.
- Avoid placing affected ECDSA key operations beside untrusted local users or VMs.
- Consider key rotation after remediation if local or co-tenant exposure was plausible.
Validation and detection
- Confirm whether MatrixSSL is present and whether the version is through 3.9.5 Open.
- Determine whether affected systems perform ECDSA signing with sensitive long-term keys.
- Review whether untrusted users or VMs can share the same physical host.
- Check vendor advisories for patch status before declaring remediation complete.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2018-12439 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://www.nccgroup.trust/us/our-research/technical-advisory-return-of-the-hidden-number-problem/CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.