# CVE-2023-54050: ubifs: Fix memleak when insert_old_idx() failed

> A memory leak in the Linux kernel UBIFS filesystem can lead to resource exhaustion and denial of service when index insertion fails.

- **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:** 24 Dec 2025
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2023-54050, DEBIAN-CVE-2023-54050, GHSA-4h8w-644c-qcrw, UBUNTU-CVE-2023-54050

## What is CVE-2023-54050?

CVE-2023-54050 is a high-severity denial of service vulnerability in Linux, published on 24 Dec 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:

ubifs: Fix memleak when insert_old_idx() failed

Following process will cause a memleak for copied up znode:

dirty_cow_znode
  zn = copy_znode(c, znode);
  err = insert_old_idx(c, zbr->lnum, zbr->offs);
  if (unlikely(err))
     return ERR_PTR(err);   // No one refers to zn.

Fetch a reproducer in [Link].

Function copy_znode() is split into 2 parts: resource allocation
and znode replacement, insert_old_idx() is split in similar way,
so resource cleanup could be done in error handling path without
corrupting metadata(mem & disk).
It's okay that old index inserting is put behind of add_idx_dirt(),
old index is used in layout_leb_in_gaps(), so the two processes do
not depend on each other.

## Which versions are affected by CVE-2023-54050?


## How do I fix CVE-2023-54050?

Apply the vendor's patch.

## Is CVE-2023-54050 being exploited?

There is no known exploitation of CVE-2023-54050 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2023-54050 and fix it if it is affected.

What it is: CVE-2023-54050 is a high-severity denial of service vulnerability in Linux, published on 24 Dec 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-2023-54050 in the wild and no public exploit code.

Affected product: Linux. 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-2023-54050/ (Markdown: https://insights.sbomify.com/CVE-2023-54050/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-54050
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-54050
- OSV: https://osv.dev/vulnerability/CVE-2023-54050

---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-54050/
Summaries are generated and may contain mistakes; the official description above is the record.