Security readout for executives and security teams
Plain-English summary
This Linux KVM issue can leave AMD SEV guest contexts undecommissioned after a failed receive start operation. The practical risk is operational: SEV firmware resources can leak, causing later confidential VM launches to fail. It is not listed as known exploited in KEV.
Executive priority
Treat this as a targeted infrastructure reliability issue, not an internet-wide emergency. Patch affected AMD SEV virtualization hosts through normal kernel maintenance, with higher priority where confidential computing workloads depend on reliable SEV guest launches.
Technical view
In KVM SVM SEV handling, sev_receive_start created a new guest context but did not call sev_decommission when ASID binding failed. The source states this can leak firmware memory and prevent allocation of future SEV guest contexts. The CVSS vector is local, low complexity, no user interaction, with low integrity and availability impact.
Likely exposure
Exposure is most relevant to Linux virtualization hosts using KVM on AMD SVM/SEV, especially environments using SEV receive or migration workflows. Systems not using KVM with AMD SEV are unlikely to be meaningfully exposed based on the provided sources.
Exploitation context
The source bundle does not show active exploitation, KEV listing, exploit availability, or remote attack evidence. The described impact is resource leakage and subsequent SEV launch failures after a specific failure path, not direct data disclosure.
Researcher notes
The evidence is limited to the CVE description, CVSS data, and Linux stable commit references. Version metadata in the bundle is sparse, so use vendor kernel advisories to determine exact package exposure. Avoid assuming affected status from upstream version numbers alone.
Mitigation direction
- Apply Linux kernel updates containing the referenced stable fixes.
- Prioritize AMD SEV/KVM virtualization hosts over non-SEV Linux systems.
- Check distribution vendor advisories for backported fixes and affected package versions.
- Monitor for SEV guest launch failures after receive or migration operations.
- If patching is delayed, follow vendor guidance for SEV operational risk.
Validation and detection
- Inventory Linux hosts running KVM with AMD SVM/SEV enabled.
- Compare running kernel packages against distribution advisories and the referenced stable fixes.
- Review virtualization logs for SEV receive, ASID binding, or launch failure patterns.
- Confirm patched hosts can create or receive SEV guests successfully.
- Document non-SEV systems as lower priority with supporting configuration evidence.
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-772: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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-2021-47389 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
- Medium
- CVSS
- 5.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
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.
SSVC decision data
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:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L2.52.5CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
5.1MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/stable/c/efd7866e114dcb44f86d151e843f8276b7efbc67CVE reference, Linux
- https://git.kernel.org/stable/c/f1815e0aa770f2127c5df31eb5c2f0e37b60fa77CVE reference, Linux
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.
Missing Release of Resource after Effective Lifetime
Missing Release of Resource after Effective Lifetime represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.