# CVE-2025-22083: vhost-scsi: Fix handling of multiple calls to vhost_scsi_set_endpoint

> A use-after-free vulnerability in the Linux kernel's vhost-scsi driver allows attackers to cause denial of service or potentially execute code via multiple endpoint calls.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:** 16 Apr 2025
- **Updated:** 15 Oct 2026
- **Also known as:** BELL-CVE-2025-22083, DEBIAN-CVE-2025-22083, GHSA-vcjc-q999-g4p2, ROOT-OS-DEBIAN-11-CVE-2025-22083, ROOT-OS-DEBIAN-12-CVE-2025-22083, ROOT-OS-UBUNTU-2204-CVE-2025-22083, ROOT-OS-UBUNTU-2404-CVE-2025-22083, UBUNTU-CVE-2025-22083

## What is CVE-2025-22083?

CVE-2025-22083 is a high-severity use after free vulnerability in Linux kernel, published on 16 Apr 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:

vhost-scsi: Fix handling of multiple calls to vhost_scsi_set_endpoint

If vhost_scsi_set_endpoint is called multiple times without a
vhost_scsi_clear_endpoint between them, we can hit multiple bugs
found by Haoran Zhang:

1. Use-after-free when no tpgs are found:

This fixes a use after free that occurs when vhost_scsi_set_endpoint is
called more than once and calls after the first call do not find any
tpgs to add to the vs_tpg. When vhost_scsi_set_endpoint first finds
tpgs to add to the vs_tpg array match=true, so we will do:

vhost_vq_set_backend(vq, vs_tpg);
...

kfree(vs->vs_tpg);
vs->vs_tpg = vs_tpg;

If vhost_scsi_set_endpoint is called again and no tpgs are found
match=false so we skip the vhost_vq_set_backend call leaving the
pointer to the vs_tpg we then free via:

kfree(vs->vs_tpg);
vs->vs_tpg = vs_tpg;

If a scsi request is then sent we do:

vhost_scsi_handle_vq -> vhost_scsi_get_req -> vhost_vq_get_backend

which sees the vs_tpg we just did a kfree on.

2. Tpg dir removal hang:

This patch fixes an issue where we cannot remove a LIO/target layer
tpg (and structs above it like the target) dir due to the refcount
dropping to -1.

The problem is that if vhost_scsi_set_endpoint detects a tpg is already
in the vs->vs_tpg array or if the tpg has been removed so
target_depend_item fails, the undepend goto handler will do
target_undepend_item on all tpgs in the vs_tpg array dropping their
refcount to 0. At this time vs_tpg contains both the tpgs we have added
in the current vhost_scsi_set_endpoint call as well as tpgs we added in
previous calls which are also in vs->vs_tpg.

Later, when vhost_scsi_clear_endpoint runs it will do
target_undepend_item on all the tpgs in the vs->vs_tpg which will drop
their refcount to -1. Userspace will then not be able to remove the tpg
and will hang when it tries to do rmdir on the tpg dir.

3. Tpg leak:

This fixes a bug where we can leak tpgs and cause them to be
un-removable because the target name is overwritten when
vhost_scsi_set_endpoint is called multiple times but with different
target names.

The bug occurs if a user has called VHOST_SCSI_SET_ENDPOINT and setup
a vhost-scsi device to target/tpg mapping, then calls
VHOST_SCSI_SET_ENDPOINT again with a new target name that has tpgs we
haven't seen before (target1 has tpg1 but target2 has tpg2). When this
happens we don't teardown the old target tpg mapping and just overwrite
the target name and the vs->vs_tpg array. Later when we do
vhost_scsi_clear_endpoint, we are passed in either target1 or target2's
name and we will only match that target's tpgs when we loop over the
vs->vs_tpg. We will then return from the function without doing
target_undepend_item on the tpgs.

Because of all these bugs, it looks like being able to call
vhost_scsi_set_endpoint multiple times was never supported. The major
user, QEMU, already has checks to prevent this use case. So to fix the
issues, this patch prevents vhost_scsi_set_endpoint from being called
if it's already successfully added tpgs. To add, remove or change the
tpg config or target name, you must do a vhost_scsi_clear_endpoint
first.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2025-22083?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2025-22083?

Apply the vendor's patch.

## Is CVE-2025-22083 being exploited?

There is no known exploitation of CVE-2025-22083 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-2025-22083 and fix it if it is affected.

What it is: CVE-2025-22083 is a high-severity use after free vulnerability in Linux kernel, published on 16 Apr 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-2025-22083 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-2025-22083/ (Markdown: https://insights.sbomify.com/CVE-2025-22083/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-22083
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-22083
- OSV: https://osv.dev/vulnerability/CVE-2025-22083

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-22083/
Summaries are generated and may contain mistakes; the official description above is the record.