# CVE-2024-46689: soc: qcom: cmd-db: Map shared memory as WC, not WB

> A Linux kernel vulnerability causes a denial of service via an endless loop in Trust Zone when using non-default hypervisors like Xen or KVM.

- **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:** 13 Sep 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-49377, BELL-CVE-2024-46689, DEBIAN-CVE-2024-46689, GHSA-9hw6-9frh-hxrg, UBUNTU-CVE-2024-46689

## What is CVE-2024-46689?

CVE-2024-46689 is a medium-severity denial of service vulnerability in Linux kernel, published on 13 Sep 2024. 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:

soc: qcom: cmd-db: Map shared memory as WC, not WB

Linux does not write into cmd-db region. This region of memory is write
protected by XPU. XPU may sometime falsely detect clean cache eviction
as "write" into the write protected region leading to secure interrupt
which causes an endless loop somewhere in Trust Zone.

The only reason it is working right now is because Qualcomm Hypervisor
maps the same region as Non-Cacheable memory in Stage 2 translation
tables. The issue manifests if we want to use another hypervisor (like
Xen or KVM), which does not know anything about those specific mappings.

Changing the mapping of cmd-db memory from MEMREMAP_WB to MEMREMAP_WT/WC
removes dependency on correct mappings in Stage 2 tables. This patch
fixes the issue by updating the mapping to MEMREMAP_WC.

I tested this on SA8155P with Xen.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2024-46689?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-46689?

Apply the vendor's patch.

## Is CVE-2024-46689 being exploited?

There is no known exploitation of CVE-2024-46689 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-2024-46689 and fix it if it is affected.

What it is: CVE-2024-46689 is a medium-severity denial of service vulnerability in Linux kernel, published on 13 Sep 2024. 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-2024-46689 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-2024-46689/ (Markdown: https://insights.sbomify.com/CVE-2024-46689/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-46689
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-46689
- OSV: https://osv.dev/vulnerability/CVE-2024-46689

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-46689/
Summaries are generated and may contain mistakes; the official description above is the record.
