# CVE-2022-48674: erofs: fix pcluster use-after-free on UP platforms

> A use-after-free vulnerability in the Linux kernel EROFS filesystem on uniprocessor systems allows attackers to cause a denial of service or potentially execute code.

- **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:** 3 May 2024
- **Updated:** 5 Aug 2026
- **Also known as:** DEBIAN-CVE-2022-48674, GHSA-5cqc-m9rw-57r9, ROOT-OS-DEBIAN-11-CVE-2022-48674, UBUNTU-CVE-2022-48674

## What is CVE-2022-48674?

CVE-2022-48674 is a high-severity use after free vulnerability in Linux kernel, published on 3 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:

erofs: fix pcluster use-after-free on UP platforms

During stress testing with CONFIG_SMP disabled, KASAN reports as below:

==================================================================
BUG: KASAN: use-after-free in __mutex_lock+0xe5/0xc30
Read of size 8 at addr ffff8881094223f8 by task stress/7789

CPU: 0 PID: 7789 Comm: stress Not tainted 6.0.0-rc1-00002-g0d53d2e882f9 #3
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
Call Trace:
 <TASK>
..
 __mutex_lock+0xe5/0xc30
..
 z_erofs_do_read_page+0x8ce/0x1560
..
 z_erofs_readahead+0x31c/0x580
..
Freed by task 7787
 kasan_save_stack+0x1e/0x40
 kasan_set_track+0x20/0x30
 kasan_set_free_info+0x20/0x40
 __kasan_slab_free+0x10c/0x190
 kmem_cache_free+0xed/0x380
 rcu_core+0x3d5/0xc90
 __do_softirq+0x12d/0x389

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40
 __kasan_record_aux_stack+0x97/0xb0
 call_rcu+0x3d/0x3f0
 erofs_shrink_workstation+0x11f/0x210
 erofs_shrink_scan+0xdc/0x170
 shrink_slab.constprop.0+0x296/0x530
 drop_slab+0x1c/0x70
 drop_caches_sysctl_handler+0x70/0x80
 proc_sys_call_handler+0x20a/0x2f0
 vfs_write+0x555/0x6c0
 ksys_write+0xbe/0x160
 do_syscall_64+0x3b/0x90

The root cause is that erofs_workgroup_unfreeze() doesn't reset to
orig_val thus it causes a race that the pcluster reuses unexpectedly
before freeing.

Since UP platforms are quite rare now, such path becomes unnecessary.
Let's drop such specific-designed path directly instead.

Weakness: CWE-416 (Use After Free)

## Which versions are affected by CVE-2022-48674?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2022-48674?

Apply the vendor's patch.

## Is CVE-2022-48674 being exploited?

There is no known exploitation of CVE-2022-48674 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-2022-48674 and fix it if it is affected.

What it is: CVE-2022-48674 is a high-severity use after free vulnerability in Linux kernel, published on 3 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-2022-48674 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-2022-48674/ (Markdown: https://insights.sbomify.com/CVE-2022-48674/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2022-48674
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2022-48674
- OSV: https://osv.dev/vulnerability/CVE-2022-48674

---
From sbomify Insights: https://insights.sbomify.com/CVE-2022-48674/
Summaries are generated and may contain mistakes; the official description above is the record.