# CVE-2024-48881: bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again

> A NULL pointer dereference in the Linux kernel bcache module can cause a system crash during cache set flushing.

- **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:** 11 Jan 2025
- **Updated:** 15 Oct 2026
- **Also known as:** AZL-56139, AZL-56157, BELL-CVE-2024-48881, DEBIAN-CVE-2024-48881, GHSA-2g99-pch7-3284, UBUNTU-CVE-2024-48881

## What is CVE-2024-48881?

CVE-2024-48881 is a medium-severity vulnerability in Linux kernel, published on 11 Jan 2025. 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:

bcache: revert replacing IS_ERR_OR_NULL with IS_ERR again

Commit 028ddcac477b ("bcache: Remove unnecessary NULL point check in
node allocations") leads a NULL pointer deference in cache_set_flush().

1721         if (!IS_ERR_OR_NULL(c->root))
1722                 list_add(&c->root->list, &c->btree_cache);

>From the above code in cache_set_flush(), if previous registration code
fails before allocating c->root, it is possible c->root is NULL as what
it is initialized. __bch_btree_node_alloc() never returns NULL but
c->root is possible to be NULL at above line 1721.

This patch replaces IS_ERR() by IS_ERR_OR_NULL() to fix this.

Weakness: CWE-476 (NULL Pointer Dereference)

## Which versions are affected by CVE-2024-48881?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-48881?

Apply the vendor's patch.

## Is CVE-2024-48881 being exploited?

There is no known exploitation of CVE-2024-48881 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-2024-48881 and fix it if it is affected.

What it is: CVE-2024-48881 is a medium-severity vulnerability in Linux kernel, published on 11 Jan 2025. 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-2024-48881 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-2024-48881/ (Markdown: https://insights.sbomify.com/CVE-2024-48881/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-48881
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-48881
- OSV: https://osv.dev/vulnerability/CVE-2024-48881

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-48881/
Summaries are generated and may contain mistakes; the official description above is the record.