Security readout for executives and security teams
Plain-English summary
This is a Linux kernel availability issue in NVMe over TCP handling. Under specific local storage networking conditions, incorrect locking can deadlock the system path handling TCP state changes. Business impact is most relevant for hosts using NVMe/TCP target and initiator functionality, especially storage or lab systems where both roles run together.
Executive priority
Treat as targeted operational risk, not broad emergency patching. Prioritize storage infrastructure, virtualization hosts, and systems using NVMe over TCP. If those roles are absent, urgency is lower, but kernel lifecycle patching should still include the fix.
Technical view
The nvmet-tcp state_change socket callback used a write lock even though it did not modify TCP connection state. Lockdep reported inconsistent softirq locking and a possible deadlock when nvmet-tcp and nvme-tcp ran on the same system. The source indicates the fix changes locking behavior, not protocol parsing or authentication.
Likely exposure
Exposure appears limited to Linux systems using NVMe over TCP, particularly where nvmet-tcp and nvme-tcp operate on the same host. The provided affected version data references Linux 5.0 through 5.13-era kernels and stable backport commits, but distro kernel backports should be treated as authoritative.
Exploitation context
The source bundle does not report active exploitation, and KEV is false. The documented trigger is a lockdep-observed deadlock during NVMe/TCP teardown or state-change interactions, not a described remote exploit path. Evidence supports availability risk under specific operational conditions.
Researcher notes
The key technical detail is lock type misuse in nvmet_tcp_state_change. The evidence shows inconsistent IN-SOFTIRQ write versus SOFTIRQ read lock usage on AF_INET clock locking. Source version metadata is incomplete, so validation should rely on fixed commits and downstream advisories.
Mitigation direction
- Update affected Linux kernels through vendor or distribution-supported packages.
- Confirm the deployed kernel contains the referenced stable fix or a downstream backport.
- Prioritize systems running NVMe/TCP target or initiator modules.
- Review vendor guidance before changing storage topology as a workaround.
Validation and detection
- Inventory Linux hosts using NVMe/TCP target or initiator functionality.
- Check kernel versions against distribution advisories and fixed backport status.
- Identify hosts running both nvmet-tcp and nvme-tcp roles.
- Review logs for lockdep warnings, deadlocks, or NVMe/TCP teardown hangs.
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-2021-47041 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/999d606a820c36ae9b9e9611360c8b3d8d4bb777CVE reference, Linux
- https://git.kernel.org/stable/c/60ade0d56b06537a28884745059b3801c78e03bcCVE reference, Linux
- https://git.kernel.org/stable/c/06beaa1a9f6e501213195e47c30416032fd2bbd5CVE reference, Linux
- https://git.kernel.org/stable/c/906c538340dde6d891df89fe7dac8eaa724e40daCVE reference, Linux
- https://git.kernel.org/stable/c/b5332a9f3f3d884a1b646ce155e664cc558c1722CVE 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.