Security readout for executives and security teams
Plain-English summary
This issue affects IBM AIX and VIOS systems and could let a local, non-privileged user crash or disrupt the system through the AIX kernel. The main business impact is availability loss, not data theft or tampering, based on the provided CVSS and description.
Executive priority
Treat this as a moderate availability risk. It should be remediated during planned maintenance, with faster handling for shared, critical, or multi-user AIX and VIOS systems.
Technical view
CVE-2021-38994 is a local denial-of-service vulnerability in the AIX kernel affecting IBM AIX 7.1, 7.2, 7.3, and VIOS 3.1. The CVSS 3.0 score is 6.2 with local attack vector, low complexity, no user interaction, and high availability impact.
Likely exposure
Exposure is most relevant where affected AIX or VIOS hosts allow local interactive access by non-administrative users. Internet-facing exposure is not indicated by the source bundle because the attack vector is local.
Exploitation context
The source bundle does not show CISA KEV listing or cite active exploitation. It describes a local denial-of-service condition, so realistic exploitation depends on an attacker already having local access to an affected system.
Researcher notes
The provided sources do not include a CWE, exploit details, or concrete patch identifiers. Analysis should stay focused on local kernel denial of service, affected IBM versions, and vendor advisory validation.
Mitigation direction
- Identify AIX 7.1, 7.2, 7.3, and VIOS 3.1 systems.
- Review IBM advisory 6558948 for the applicable official fixes.
- Apply vendor-recommended AIX or VIOS maintenance updates.
- Restrict unnecessary local shell access on affected hosts.
- Prioritize systems supporting critical business workloads.
Validation and detection
- Inventory AIX and VIOS versions across IBM Power environments.
- Compare installed levels against IBM advisory guidance.
- Confirm whether non-privileged local users can access affected hosts.
- Check change records for applied IBM maintenance updates.
- Monitor affected systems for unexplained availability disruptions.
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-2021-38994 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
- 6.2 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:L/UI:N/C:N/A:H/I:N/S:U/PR:N/AC:L/RC:C/RL:O/E:U
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:3.0/AV:L/UI:N/C:N/A:H/I:N/S:U/PR:N/AC:L/RC:C/RL:O/E:U2.53.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
6.2MediumVector: CVSS:3.0/AV:L/UI:N/C:N/A:H/I:N/S:U/PR:N/AC:L/RC:C/RL:O/E:U
Source materials
- CVE List V5 sourceCVE List V5
- https://www.ibm.com/support/pages/node/6558948CVE reference · x_refsource_CONFIRM
- ibm-aix-cve202138994-dos (213072)CVE reference · vdb-entry, x_refsource_XF
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.