Security readout for executives and security teams
Plain-English summary
Huawei reported a critical DRM flaw affecting HarmonyOS 2.0 and EMUI 12.0.0. The public description says failed secure-memory attribute verification can cause abnormal video playback. The CVSS rating is severe, but the public sources do not explain broader compromise details.
Executive priority
Treat this as high-priority patch governance for Huawei device fleets because the vendor assigned critical CVSS impact. Business urgency depends on whether affected Huawei OS versions exist in managed or bring-your-own-device environments.
Technical view
CVE-2021-46851 is a CWE-284 improper-access-control issue in Huawei’s DRM module involving verification of secure memory attributes. Huawei lists HarmonyOS 2.0 and EMUI 12.0.0 as affected. The CVSS 3.1 vector is network, low complexity, no privileges, no user interaction, with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely in organizations with Huawei phones or devices running HarmonyOS 2.0 or EMUI 12.0.0. The source bundle does not provide CPEs, model-level scope, or deployment prevalence, so inventory confirmation is required.
Exploitation context
The source bundle does not show CISA KEV listing, active exploitation, public exploit availability, or exploitation mechanics. CVSS indicates network reachability and no required user interaction, but public Huawei text only states abnormal video playback as the observed consequence.
Researcher notes
Public evidence is sparse. The description identifies DRM secure-memory attribute verification and CWE-284, but does not disclose root cause, affected components by model, patch identifiers, or exploitation detail. Avoid assuming impacts beyond the CVSS vector and Huawei’s abnormal-video-playback statement.
Mitigation direction
- Review Huawei’s November 2022 bulletin for affected models and fixed builds.
- Update HarmonyOS 2.0 and EMUI 12.0.0 devices to vendor-fixed firmware where available.
- Prioritize managed Huawei devices used for sensitive communications or regulated data.
- If no update exists, follow Huawei guidance and reduce exposure until remediated.
Validation and detection
- Inventory Huawei devices and record OS family, version, model, and patch level.
- Compare device builds against Huawei’s November 2022 security bulletin.
- Confirm whether any fleet devices remain on HarmonyOS 2.0 or EMUI 12.0.0.
- Document exceptions where vendor fixes are unavailable or unsupported.
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.
CWE-284: Authorization and privilege behavior lookup
Authorization weaknesses can support privilege escalation and valid-account review, depending on exploit path. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-46851 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
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
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.
Improper Access Control
Improper Access Control represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.