# CVE-2022-49894: cxl/region: Fix region HPA ordering validation

> A null pointer dereference in the Linux kernel CXL region validation allows local attackers to cause a system crash.

- **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:** 1 May 2025
- **Updated:** 11 May 2026
- **Also known as:** DEBIAN-CVE-2022-49894, GHSA-8w66-gh7h-jgjh, UBUNTU-CVE-2022-49894

## What is CVE-2022-49894?

CVE-2022-49894 is a medium-severity vulnerability in Linux kernel, published on 1 May 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:

cxl/region: Fix region HPA ordering validation

Some regions may not have any address space allocated. Skip them when
validating HPA order otherwise a crash like the following may result:

 devm_cxl_add_region: cxl_acpi cxl_acpi.0: decoder3.4: created region9
 BUG: kernel NULL pointer dereference, address: 0000000000000000
 [..]
 RIP: 0010:store_targetN+0x655/0x1740 [cxl_core]
 [..]
 Call Trace:
  <TASK>
  kernfs_fop_write_iter+0x144/0x200
  vfs_write+0x24a/0x4d0
  ksys_write+0x69/0xf0
  do_syscall_64+0x3a/0x90

store_targetN+0x655/0x1740:
alloc_region_ref at drivers/cxl/core/region.c:676
(inlined by) cxl_port_attach_region at drivers/cxl/core/region.c:850
(inlined by) cxl_region_attach at drivers/cxl/core/region.c:1290
(inlined by) attach_target at drivers/cxl/core/region.c:1410
(inlined by) store_targetN at drivers/cxl/core/region.c:1453

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2022-49894?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-49894?

Apply the vendor's patch.

## Is CVE-2022-49894 being exploited?

There is no known exploitation of CVE-2022-49894 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-2022-49894 and fix it if it is affected.

What it is: CVE-2022-49894 is a medium-severity vulnerability in Linux kernel, published on 1 May 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-2022-49894 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-2022-49894/ (Markdown: https://insights.sbomify.com/CVE-2022-49894/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-49894
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-49894
- OSV: https://osv.dev/vulnerability/CVE-2022-49894

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-49894/
Summaries are generated and may contain mistakes; the official description above is the record.