Security readout for executives and security teams
Plain-English summary
This Linux kernel issue affects RDMA flow-rule creation. A user-supplied port value was not properly validated, which could trigger a kernel oops in the mlx5_ib RDMA driver. The available sources do not provide CVSS scoring, confirmed exploitation, or detailed business impact beyond the kernel crash evidence.
Executive priority
Treat this as a targeted infrastructure hygiene item, not an internet-wide emergency based on current evidence. Prioritize patch verification on RDMA-enabled Linux servers, especially high-availability compute, storage, or networking systems.
Technical view
CVE-2021-47265 is a Linux kernel RDMA/uverbs validation flaw. The fix validates the user-provided port before creating a flow rule, preventing mlx5_ib from reaching an invalid state that can produce the documented oops call trace during ib_uverbs flow creation.
Likely exposure
Exposure is most likely on Linux systems using RDMA/uverbs with mlx5_ib-capable hardware and affected kernel builds. Exact exposure depends on distro backports and whether RDMA interfaces are present and accessible.
Exploitation context
The source bundle shows no CISA KEV listing and no cited evidence of active exploitation. The described impact is a kernel oops triggered through RDMA flow-rule creation, but sources do not provide exploit prerequisites or real-world attack reports.
Researcher notes
The public record is sparse: no CVSS, CWE, exploit status, or detailed affected distro mapping is provided. Analysis should focus on kernel provenance, RDMA device exposure, and whether vendor kernels include the stable commits.
Mitigation direction
- Update to a Linux kernel containing the referenced stable fixes.
- Check distribution advisories for backported fixes in supported kernel packages.
- Prioritize RDMA-enabled servers and systems using mlx5_ib hardware.
- Follow vendor guidance if kernel updates are not immediately available.
Validation and detection
- Inventory Linux kernel versions on RDMA-capable systems.
- Confirm whether mlx5_ib and ib_uverbs are present or loaded.
- Verify installed kernels include the referenced stable commits or distro backports.
- Review kernel logs for mlx5_ib or ib_uverbs oops events.
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
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CVE-2021-47265 mapping review
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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/8dc1b0e0ca204596c50bcd159ee069ae0f998176CVE reference, Linux
- https://git.kernel.org/stable/c/2adcb4c5a52a2623cd2b43efa7041e74d19f3a5eCVE 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.