CVE-2021-47378Network attack vector

Host compromise via premature queue-pair destruction

Published May 21, 2024 · Updated Aug 5, 2026

Use-after-free in Linux kernel nvme-rdma allows remote attackers controlling an NVMe-RDMA peer to crash or compromise the host. The connection-error path destroys a queue pair while its RDMA connection-manager ID remains live, so later CMA events access freed queue resources. A pre-existing or reconnecting NVMe-RDMA session is required; successful exploitation enables kernel memory access, code execution, or a panic.

CVSS severity9.8
Critical
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Use-after-free in Linux kernel nvme-rdma allows remote attackers controlling an NVMe-RDMA peer to crash or compromise the host. The connection-error path destroys a queue pair while its RDMA connection-manager ID remains live, so later CMA events access freed queue resources. A pre-existing or reconnecting NVMe-RDMA session is required; successful exploitation enables kernel memory access, code execution, or a panic.

The record

CVE
CVE-2021-47378
Published
May 21, 2024
Updated
Aug 5, 2026
Vendor
The Linux Kernel Organization
Product
Linux
Classifications
CWE-416, T1499
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 21, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 5, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=4.8
  2. Affected versionversion=7110230719602852481c2793d054f866b2bf4a2b <9817d763dbe15327b9b3ff4404fa6f27f927e744
  3. Affected versionversion=7110230719602852481c2793d054f866b2bf4a2b <d268a182c56e8361e19fb781137411643312b994
  4. Affected versionversion=7110230719602852481c2793d054f866b2bf4a2b <ecf0dc5a904830c926a64feffd8e01141f89822f

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Linux Kernel Organization · Linuxversion=4.8; version=7110230719602852481c2793d054f866b2bf4a2b <9817d763dbe15327b9b3ff4404fa6f27f927e744; version=7110230719602852481c2793d054f866b2bf4a2b <d268a182c56e8361e19fb781137411643312b994; version=7110230719602852481c2793d054f866b2bf4a2b <ecf0dc5a904830c926a64feffd8e01141f89822f
The Linux Kernel Organization · Linux Kernelversion=1da177e4c3f4

Published CVSS scores

9.8Linux CNACVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1499Endpoint Denial of Service

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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