# CVE-2024-56611: mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MM

> A local attacker can trigger a kernel crash by exploiting a null pointer dereference in the memory policy migration code.

- **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:** 27 Dec 2024
- **Updated:** 11 May 2026
- **Also known as:** AZL-54806, AZL-54872, BELL-CVE-2024-56611, DEBIAN-CVE-2024-56611, GHSA-vmhm-g2hv-x7wj, ROOT-OS-DEBIAN-11-CVE-2024-56611, ROOT-OS-DEBIAN-12-CVE-2024-56611, ROOT-OS-UBUNTU-2204-CVE-2024-56611, UBUNTU-CVE-2024-56611

## What is CVE-2024-56611?

CVE-2024-56611 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 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:

mm/mempolicy: fix migrate_to_node() assuming there is at least one VMA in a MM

We currently assume that there is at least one VMA in a MM, which isn't
true.

So we might end up having find_vma() return NULL, to then de-reference
NULL.  So properly handle find_vma() returning NULL.

This fixes the report:

Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
CPU: 1 UID: 0 PID: 6021 Comm: syz-executor284 Not tainted 6.12.0-rc7-syzkaller-00187-gf868cd251776 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024
RIP: 0010:migrate_to_node mm/mempolicy.c:1090 [inline]
RIP: 0010:do_migrate_pages+0x403/0x6f0 mm/mempolicy.c:1194
Code: ...
RSP: 0018:ffffc9000375fd08 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffc9000375fd78 RCX: 0000000000000000
RDX: ffff88807e171300 RSI: dffffc0000000000 RDI: ffff88803390c044
RBP: ffff88807e171428 R08: 0000000000000014 R09: fffffbfff2039ef1
R10: ffffffff901cf78f R11: 0000000000000000 R12: 0000000000000003
R13: ffffc9000375fe90 R14: ffffc9000375fe98 R15: ffffc9000375fdf8
FS:  00005555919e1380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555919e1ca8 CR3: 000000007f12a000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 kernel_migrate_pages+0x5b2/0x750 mm/mempolicy.c:1709
 __do_sys_migrate_pages mm/mempolicy.c:1727 [inline]
 __se_sys_migrate_pages mm/mempolicy.c:1723 [inline]
 __x64_sys_migrate_pages+0x96/0x100 mm/mempolicy.c:1723
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

[akpm@linux-foundation.org: add unlikely()]

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-56611?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-56611?

Apply the vendor's patch.

## Is CVE-2024-56611 being exploited?

There is no known exploitation of CVE-2024-56611 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-2024-56611 and fix it if it is affected.

What it is: CVE-2024-56611 is a medium-severity vulnerability in Linux kernel, published on 27 Dec 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-2024-56611 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-2024-56611/ (Markdown: https://insights.sbomify.com/CVE-2024-56611/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-56611
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-56611
- OSV: https://osv.dev/vulnerability/CVE-2024-56611

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-56611/
Summaries are generated and may contain mistakes; the official description above is the record.