# CVE-2021-47378: nvme-rdma: destroy cm id before destroy qp to avoid use after free

> A use-after-free vulnerability in the Linux kernel's NVMe RDMA driver allows attackers to potentially execute code or cause a system crash.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2021-47378, GHSA-7fq3-h5p4-7j98, SUSE-SU-2024:3014-1, SUSE-SU-2024:3021-1, SUSE-SU-2024:3027-1, SUSE-SU-2024:3040-1, UBUNTU-CVE-2021-47378

## What is CVE-2021-47378?

CVE-2021-47378 is a critical use after free vulnerability in Linux kernel, published on 21 May 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

In the Linux kernel, the following vulnerability has been resolved:

nvme-rdma: destroy cm id before destroy qp to avoid use after free

We should always destroy cm_id before destroy qp to avoid to get cma
event after qp was destroyed, which may lead to use after free.
In RDMA connection establishment error flow, don't destroy qp in cm
event handler.Just report cm_error to upper level, qp will be destroy
in nvme_rdma_alloc_queue() after destroy cm id.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2021-47378?

It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `kgraft-patch-SLE12-SP5_Update_47` | SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 14-2.1 |
| `kgraft-patch-SLE12-SP5_Update_48` | SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 13-2.1 |
| `kgraft-patch-SLE12-SP5_Update_49` | SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 12-2.1 |
| `kgraft-patch-SLE12-SP5_Update_53` | SUSE:Linux Enterprise Live Patching 12 SP5 | All versions | 8-2.1 |

Products: Linux kernel.

## How do I fix CVE-2021-47378?

Apply the vendor's patch.

## Is CVE-2021-47378 being exploited?

There is no known exploitation of CVE-2021-47378 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-47378 and fix it if it is affected.

What it is: CVE-2021-47378 is a critical use after free vulnerability in Linux kernel, published on 21 May 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2021-47378 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2021-47378/ (Markdown: https://insights.sbomify.com/CVE-2021-47378/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-47378
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-47378
- OSV: https://osv.dev/vulnerability/CVE-2021-47378

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-47378/
Summaries are generated and may contain mistakes; the official description above is the record.