# CVE-2024-27070: f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault

> A use-after-free vulnerability in the Linux kernel's f2fs filesystem allows local attackers to potentially execute arbitrary code or escalate privileges.

- **Severity:** High 7.1 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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:** 1 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-27070, GHSA-8xwv-9gjh-23gh, UBUNTU-CVE-2024-27070

## What is CVE-2024-27070?

CVE-2024-27070 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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:

f2fs: fix to avoid use-after-free issue in f2fs_filemap_fault

syzbot reports a f2fs bug as below:

BUG: KASAN: slab-use-after-free in f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49
Read of size 8 at addr ffff88807bb22680 by task syz-executor184/5058

CPU: 0 PID: 5058 Comm: syz-executor184 Not tainted 6.7.0-syzkaller-09928-g052d534373b7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:377 [inline]
 print_report+0x163/0x540 mm/kasan/report.c:488
 kasan_report+0x142/0x170 mm/kasan/report.c:601
 f2fs_filemap_fault+0xd1/0x2c0 fs/f2fs/file.c:49
 __do_fault+0x131/0x450 mm/memory.c:4376
 do_shared_fault mm/memory.c:4798 [inline]
 do_fault mm/memory.c:4872 [inline]
 do_pte_missing mm/memory.c:3745 [inline]
 handle_pte_fault mm/memory.c:5144 [inline]
 __handle_mm_fault+0x23b7/0x72b0 mm/memory.c:5285
 handle_mm_fault+0x27e/0x770 mm/memory.c:5450
 do_user_addr_fault arch/x86/mm/fault.c:1364 [inline]
 handle_page_fault arch/x86/mm/fault.c:1507 [inline]
 exc_page_fault+0x456/0x870 arch/x86/mm/fault.c:1563
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:570

The root cause is: in f2fs_filemap_fault(), vmf->vma may be not alive after
filemap_fault(), so it may cause use-after-free issue when accessing
vmf->vma->vm_flags in trace_f2fs_filemap_fault(). So it needs to keep vm_flags
in separated temporary variable for tracepoint use.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2024-27070?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-27070?

Apply the vendor's patch.

## Is CVE-2024-27070 being exploited?

There is no known exploitation of CVE-2024-27070 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-2024-27070 and fix it if it is affected.

What it is: CVE-2024-27070 is a high-severity use after free vulnerability in Linux kernel, published on 1 May 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-2024-27070 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-2024-27070/ (Markdown: https://insights.sbomify.com/CVE-2024-27070/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-27070
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-27070
- OSV: https://osv.dev/vulnerability/CVE-2024-27070

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-27070/
Summaries are generated and may contain mistakes; the official description above is the record.
