Security readout for executives and security teams
Plain-English summary
This CVE affects certain older Samsung phones using Android 7.0 or 8.0 on specified Exynos chipsets. The issue is a cryptographic side-channel risk: AES-GCM operations in Keymaster used lookup tables instead of the Cryptography Extension, allowing cache attacks in some conditions. No active exploitation is cited in the provided sources.
Executive priority
Treat this as a targeted mobile cryptography risk for older Samsung fleets, not an internet-wide emergency. Prioritize identifying unsupported affected devices and removing them from sensitive use if updates cannot be confirmed.
Technical view
Samsung SVE-2018-12761 describes cache attacks against the Keymaster AES-GCM implementation on Samsung mobile devices with N(7.0) or O(8.0) and exynos7420 or Exynos 8890/8996 chipsets. The root cause stated is use of T-Tables rather than CE. CVSS, CWE, CPE, and exact fixed versions are not provided.
Likely exposure
Exposure appears limited to affected Samsung mobile devices on Android 7.0 or 8.0 with the listed Exynos chipsets. The source bundle does not identify enterprise server, cloud, or browser exposure, and the affected product metadata is incomplete.
Exploitation context
The bundle does not cite KEV listing, public exploitation, or exploit maturity. The described attack class is cache side-channel cryptanalysis against Keymaster AES-GCM, which generally implies device-specific conditions rather than broad network exploitation.
Researcher notes
The public record lacks CVSS, CWE, CPE, exact fixed build data, and exploitation evidence. Analysis should avoid broad assumptions beyond Samsung mobile devices with the named Android versions and chipsets. Vendor bulletin review is necessary for definitive remediation status.
Mitigation direction
- Review Samsung guidance for SVE-2018-12761 and CVE-2018-21058.
- Apply supported Samsung security updates for affected devices.
- Retire or isolate devices that cannot receive relevant vendor updates.
- Limit sensitive workloads on unsupported Android 7.0 or 8.0 Samsung devices.
Validation and detection
- Inventory Samsung devices by OS version and chipset.
- Check whether any devices run Android 7.0 or 8.0 on listed Exynos chipsets.
- Review security patch level against Samsung's September 2018 bulletin context.
- Confirm vendor documentation for fixed builds 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-2018-21058 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://security.samsungmobile.com/securityUpdate.smsbCVE reference · x_refsource_CONFIRM
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.