Security readout for executives and security teams
Plain-English summary
This Linux kernel issue is a memory leak in the sja1105 network switch driver when setup fails partway through. It is not described as remote code execution or privilege escalation in the provided sources. Business urgency is mainly for environments running affected kernels with this driver enabled or deployed on relevant network hardware.
Executive priority
Treat as low operational priority unless the affected driver is used in production appliances or embedded Linux platforms. Include it in normal kernel patch cycles and confirm OEM coverage for network devices.
Technical view
In sja1105_setup(), failures from sja1105_static_config_load(), sja1105_clocking_setup(), or sja1105_devlink_setup() previously returned without cleanup, leaking memory. The kernel fix adds a cleanup path. The source bundle lists Linux as affected and references stable kernel commits resolving the issue.
Likely exposure
Exposure appears limited to Linux systems using or shipping the sja1105 DSA driver. Organizations should map this CVE through their kernel or distribution advisories because the provided sources do not give a complete downstream package matrix.
Exploitation context
The bundle marks KEV as false and provides no evidence of active exploitation. The described condition depends on driver setup failure paths, so exploitation impact cannot be characterized beyond memory leakage from the supplied evidence.
Researcher notes
Evidence supports a cleanup omission causing memory leakage during setup error handling. The bundle does not include CVSS, CWE, exploitability analysis, or downstream package details, so risk scoring should remain conservative until vendor advisories add context.
Mitigation direction
- Identify systems running Linux kernels with the sja1105 DSA driver enabled or loaded.
- Apply kernel updates that include the referenced stable fixes.
- Check Linux distribution advisories for packaged kernel fix status.
- Prioritize embedded or network appliances using this driver.
- Monitor vendor guidance if kernels are supplied by an OEM.
Validation and detection
- Check deployed kernel versions against distribution advisories for CVE-2021-47158.
- Confirm whether the sja1105 driver is present, enabled, or loaded.
- Review kernel changelogs for the referenced stable commit fixes.
- Look for repeated driver setup failures in kernel logs.
- Verify patched systems no longer carry the vulnerable sja1105_setup() behavior.
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-2021-47158 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.
SSVC decision data
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/dd8609f203448ca6d58ae71461208b3f6b0329b0CVE reference, Linux
- https://git.kernel.org/stable/c/987e4ab8b8a4fcbf783069e03e7524cd39ffd563CVE reference, Linux
- https://git.kernel.org/stable/c/cec279a898a3b004411682f212215ccaea1cd0fbCVE 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.