# CVE-2024-50139: KVM: arm64: Fix shift-out-of-bounds bug

> A shift-out-of-bounds bug in the Linux kernel KVM arm64 module can cause a denial of service when running VMs with MTE enabled.

- **Severity:** High 7.9 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:L/I:L/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:** 7 Nov 2024
- **Updated:** 5 Aug 2026
- **Also known as:** AZL-53573, BELL-CVE-2024-50139, DEBIAN-CVE-2024-50139, GHSA-x935-45jx-x98p, UBUNTU-CVE-2024-50139

## What is CVE-2024-50139?

CVE-2024-50139 is a high-severity vulnerability in Linux kernel, published on 7 Nov 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:

KVM: arm64: Fix shift-out-of-bounds bug

Fix a shift-out-of-bounds bug reported by UBSAN when running
VM with MTE enabled host kernel.

UBSAN: shift-out-of-bounds in arch/arm64/kvm/sys_regs.c:1988:14
shift exponent 33 is too large for 32-bit type 'int'
CPU: 26 UID: 0 PID: 7629 Comm: qemu-kvm Not tainted 6.12.0-rc2 #34
Hardware name: IEI NF5280R7/Mitchell MB, BIOS 00.00. 2024-10-12 09:28:54 10/14/2024
Call trace:
 dump_backtrace+0xa0/0x128
 show_stack+0x20/0x38
 dump_stack_lvl+0x74/0x90
 dump_stack+0x18/0x28
 __ubsan_handle_shift_out_of_bounds+0xf8/0x1e0
 reset_clidr+0x10c/0x1c8
 kvm_reset_sys_regs+0x50/0x1c8
 kvm_reset_vcpu+0xec/0x2b0
 __kvm_vcpu_set_target+0x84/0x158
 kvm_vcpu_set_target+0x138/0x168
 kvm_arch_vcpu_ioctl_vcpu_init+0x40/0x2b0
 kvm_arch_vcpu_ioctl+0x28c/0x4b8
 kvm_vcpu_ioctl+0x4bc/0x7a8
 __arm64_sys_ioctl+0xb4/0x100
 invoke_syscall+0x70/0x100
 el0_svc_common.constprop.0+0x48/0xf0
 do_el0_svc+0x24/0x38
 el0_svc+0x3c/0x158
 el0t_64_sync_handler+0x120/0x130
 el0t_64_sync+0x194/0x198

## Which versions are affected by CVE-2024-50139?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-50139?

Apply the vendor's patch.

## Is CVE-2024-50139 being exploited?

There is no known exploitation of CVE-2024-50139 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-2024-50139 and fix it if it is affected.

What it is: CVE-2024-50139 is a high-severity vulnerability in Linux kernel, published on 7 Nov 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-2024-50139 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-2024-50139/ (Markdown: https://insights.sbomify.com/CVE-2024-50139/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-50139
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-50139
- OSV: https://osv.dev/vulnerability/CVE-2024-50139

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-50139/
Summaries are generated and may contain mistakes; the official description above is the record.