# CVE-2023-46841: x86: shadow stack vs exceptions from emulation stubs

> Missing shadow stack cleanup during exception handling in Xen hypervisor can cause system crashes when CET is enabled.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/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:** 20 Mar 2024
- **Updated:** 4 Nov 2025
- **Also known as:** ALPINE-CVE-2023-46841, DEBIAN-CVE-2023-46841, GHSA-mxh6-2xpg-m77w, SUSE-SU-2024:0934-1, SUSE-SU-2024:0935-1, UBUNTU-CVE-2023-46841, openSUSE-SU-2024:13745-1

## What is CVE-2023-46841?

CVE-2023-46841 is a medium-severity vulnerability in Fedoraproject Fedora, published on 20 Mar 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Recent x86 CPUs offer functionality named Control-flow Enforcement
Technology (CET).  A sub-feature of this are Shadow Stacks (CET-SS).
CET-SS is a hardware feature designed to protect against Return Oriented
Programming attacks. When enabled, traditional stacks holding both data
and return addresses are accompanied by so called "shadow stacks",
holding little more than return addresses.  Shadow stacks aren't
writable by normal instructions, and upon function returns their
contents are used to check for possible manipulation of a return address
coming from the traditional stack.

In particular certain memory accesses need intercepting by Xen.  In
various cases the necessary emulation involves kind of replaying of
the instruction.  Such replaying typically involves filling and then
invoking of a stub.  Such a replayed instruction may raise an
exceptions, which is expected and dealt with accordingly.

Unfortunately the interaction of both of the above wasn't right:
Recovery involves removal of a call frame from the (traditional) stack.
The counterpart of this operation for the shadow stack was missing.

## Which versions are affected by CVE-2023-46841?

It affects 2 products.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `xen` | SUSE:Linux Enterprise Micro 5.1 | All versions | 4.14.6_12-150300.3.66.1 |
| `xen` | SUSE:Linux Enterprise Micro 5.2 | All versions | 4.14.6_12-150300.3.66.1 |
| `xen` | SUSE:Linux Enterprise Micro 5.3 | All versions | 4.16.5_14-150400.4.49.1 |
| `xen` | SUSE:Linux Enterprise Micro 5.4 | All versions | 4.16.5_14-150400.4.49.1 |
| `xen` | openSUSE:Leap Micro 5.3 | All versions | 4.16.5_14-150400.4.49.1 |
| `xen` | openSUSE:Leap Micro 5.4 | All versions | 4.16.5_14-150400.4.49.1 |
| `xen` | openSUSE:Tumbleweed | All versions | 4.18.0_06-2.1 |

Products: Fedoraproject Fedora, Xen Xen.

## How do I fix CVE-2023-46841?

Apply the vendor's patch.

## Is CVE-2023-46841 being exploited?

There is no known exploitation of CVE-2023-46841 in the wild and no public exploit code.

## Other vulnerabilities in Fedoraproject Fedora

- [CVE-2024-4577](https://insights.sbomify.com/CVE-2024-4577/): PHP-CGI OS Command Injection (critical 9.8, exploited in the wild)
- [CVE-2021-39226](https://insights.sbomify.com/CVE-2021-39226/): Grafana Authentication Bypass (critical 9.8, exploited in the wild)
- [CVE-2019-5544](https://insights.sbomify.com/CVE-2019-5544/): VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow (critical 9.8, exploited in the wild)
- [CVE-2024-4947](https://insights.sbomify.com/CVE-2024-4947/): Google Chromium V8 Type Confusion (critical 9.6, exploited in the wild)
- [CVE-2024-4671](https://insights.sbomify.com/CVE-2024-4671/): Google Chromium Visuals Use-After-Free (critical 9.6, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-46841 and fix it if it is affected.

What it is: CVE-2023-46841 is a medium-severity vulnerability in Fedoraproject Fedora, published on 20 Mar 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-2023-46841 in the wild and no public exploit code.

Affected product: Fedoraproject Fedora. 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-2023-46841/ (Markdown: https://insights.sbomify.com/CVE-2023-46841/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-46841
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-46841
- OSV: https://osv.dev/vulnerability/CVE-2023-46841

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-46841/
Summaries are generated and may contain mistakes; the official description above is the record.