# CVE-2026-93098: rpmsg: glink: fix deadlock in endpoint destroy during driver detach

> A local attacker can cause a system hang by triggering a deadlock in the Linux kernel's GLINK driver during module removal.

- **Severity:** Not scored
- **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:** 17 Sep 2026
- **Updated:** 19 Oct 2026
- **Also known as:** AZL-101891, BELL-CVE-2026-93098, DEBIAN-CVE-2026-93098, GHSA-rmpv-cfqv-cmjx, UBUNTU-CVE-2026-93098

## What is CVE-2026-93098?

CVE-2026-93098 is a denial of service vulnerability in Linux, published on 17 Sep 2026. 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:

rpmsg: glink: fix deadlock in endpoint destroy during driver detach

During driver detach, the device core holds the device mutex throughout
the driver's remove callback chain.  When the rpmsg endpoint is
destroyed as part of that teardown, the GLINK endpoint destroy
implementation attempts to unregister the underlying rpmsg device.
That unregistration calls device_del(), which tries to re-acquire the
same device mutex already held higher up the stack, causing rmmod to
hang indefinitely.

The deadlock manifests with the following call chain:

[<0>] device_del+0x44/0x414  <- tries to acquire same mutex
[<0>] device_unregister+0x18/0x34
[<0>] rpmsg_unregister_device+0x28/0x4c
[<0>] qcom_glink_remove_rpmsg_device+0x70/0xc0
[<0>] qcom_glink_destroy_ept+0x58/0xbc
[<0>] rpmsg_dev_remove+0x50/0x60
[<0>] device_remove+0x4c/0x80
[<0>] device_release_driver_internal+0x1cc/0x228  <- acquires device mutex
[<0>] driver_detach+0x4c/0x98
[<0>] bus_remove_driver+0x6c/0xbc
[<0>] driver_unregister+0x30/0x60
[<0>] unregister_rpmsg_driver+0x10/0x1c
[<0>] fastrpc_exit+0x28/0x38 [fastrpc]
[<0>] __arm64_sys_delete_module+0x1b8/0x294
[<0>] invoke_syscall+0x48/0x10c
[<0>] el0_svc_common.constprop.0+0xc0/0xe0
[<0>] do_el0_svc+0x1c/0x28
[<0>] el0_svc+0x34/0x108
[<0>] el0t_64_sync_handler+0xa0/0xe4
[<0>] el0t_64_sync+0x198/0x19c

The rpmsg device unregistration inside endpoint destroy is redundant.
In both contexts where endpoint destruction is triggered:

- Driver detach path: the driver core already tears down the rpmsg
  device.

- Channel close path: the rpmsg device is already unregistered before
  endpoint destruction is reached.

Remove the redundant unregistration to fix the deadlock.

## Which versions are affected by CVE-2026-93098?


## How do I fix CVE-2026-93098?

Apply the vendor's patch.

## Is CVE-2026-93098 being exploited?

There is no known exploitation of CVE-2026-93098 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-93098 and fix it if it is affected.

What it is: CVE-2026-93098 is a denial of service vulnerability in Linux, published on 17 Sep 2026. 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-2026-93098 in the wild and no public exploit code.

Affected product: Linux. 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-2026-93098/ (Markdown: https://insights.sbomify.com/CVE-2026-93098/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-93098
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-93098
- OSV: https://osv.dev/vulnerability/CVE-2026-93098

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-93098/
Summaries are generated and may contain mistakes; the official description above is the record.