# CVE-2025-21723: scsi: mpi3mr: Fix possible crash when setting up bsg fails

> A local attacker can trigger a kernel crash in the mpi3mr driver by causing a bsg setup failure, leading to a denial of service.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 27 Feb 2025
- **Updated:** 21 Oct 2026
- **Also known as:** AZL-57982, BELL-CVE-2025-21723, DEBIAN-CVE-2025-21723, GHSA-79h6-f389-cqgv, ROOT-OS-DEBIAN-12-CVE-2025-21723, ROOT-OS-UBUNTU-2204-CVE-2025-21723, ROOT-OS-UBUNTU-2404-CVE-2025-21723, UBUNTU-CVE-2025-21723

## What is CVE-2025-21723?

CVE-2025-21723 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

scsi: mpi3mr: Fix possible crash when setting up bsg fails

If bsg_setup_queue() fails, the bsg_queue is assigned a non-NULL value.
Consequently, in mpi3mr_bsg_exit(), the condition "if(!mrioc->bsg_queue)"
will not be satisfied, preventing execution from entering
bsg_remove_queue(), which could lead to the following crash:

BUG: kernel NULL pointer dereference, address: 000000000000041c
Call Trace:
  <TASK>
  mpi3mr_bsg_exit+0x1f/0x50 [mpi3mr]
  mpi3mr_remove+0x6f/0x340 [mpi3mr]
  pci_device_remove+0x3f/0xb0
  device_release_driver_internal+0x19d/0x220
  unbind_store+0xa4/0xb0
  kernfs_fop_write_iter+0x11f/0x200
  vfs_write+0x1fc/0x3e0
  ksys_write+0x67/0xe0
  do_syscall_64+0x38/0x80
  entry_SYSCALL_64_after_hwframe+0x78/0xe2

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2025-21723?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-21723?

Apply the vendor's patch.

## Is CVE-2025-21723 being exploited?

There is no known exploitation of CVE-2025-21723 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-2025-21723 and fix it if it is affected.

What it is: CVE-2025-21723 is a medium-severity vulnerability in Linux kernel, published on 27 Feb 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-21723 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-2025-21723/ (Markdown: https://insights.sbomify.com/CVE-2025-21723/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-21723
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-21723
- OSV: https://osv.dev/vulnerability/CVE-2025-21723

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-21723/
Summaries are generated and may contain mistakes; the official description above is the record.