# CVE-2026-35353: uutils coreutils mkdir Permission Exposure Race Condition with -m

> Attackers can exploit a race condition in mkdir to access private directories created with the -m flag before permissions are correctly applied.

- **Severity:** Low 3.3 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N`)
- **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:** 22 Apr 2026
- **Updated:** 22 Apr 2026
- **Also known as:** DEBIAN-CVE-2026-35353, GHSA-mj6p-44ch-cq69, UBUNTU-CVE-2026-35353

## What is CVE-2026-35353?

CVE-2026-35353 is a low-severity vulnerability in Uutils coreutils, published on 22 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

The mkdir utility in uutils coreutils incorrectly applies permissions when using the -m flag by creating a directory with umask-derived permissions (typically 0755) before subsequently changing them to the requested mode via a separate chmod system call. In multi-user environments, this introduces a brief window where a directory intended to be private is accessible to other users, potentially leading to unauthorized data access.

Weakness: CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2026-35353?

2 open source packages ship an affected version, including uu_mkdir. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `uu_mkdir` | crates.io | All versions | 0.6.0 |
| `uu_mkdir` | crates.io | All versions | 0.6.0 |

Products: Uutils Coreutils.

## How do I fix CVE-2026-35353?

Upgrade uu_mkdir to 0.6.0 or later.

## Is CVE-2026-35353 being exploited?

There is no known exploitation of CVE-2026-35353 in the wild and no public exploit code.

## Other vulnerabilities in Uutils coreutils

- [CVE-2026-35338](https://insights.sbomify.com/CVE-2026-35338/): uutils coreutils chmod Path Traversal Bypass of --preserve-root (high 7.3)
- [CVE-2026-35368](https://insights.sbomify.com/CVE-2026-35368/): uutils coreutils chroot Local Privilege Escalation and chroot Escape in via Name Service Switch (NSS) Injection (high 7.2)
- [CVE-2026-35341](https://insights.sbomify.com/CVE-2026-35341/): uutils coreutils mkfifo Unauthorized Permission Change on Existing Files (high 7.1)
- [CVE-2026-35352](https://insights.sbomify.com/CVE-2026-35352/): uutils coreutils mkfifo Privilege Escalation via TOCTOU Race Condition (high 7.0)
- [CVE-2026-35349](https://insights.sbomify.com/CVE-2026-35349/): uutils coreutils Path-Based Safety Bypass with --preserve-root (medium 6.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-35353 and fix it if it is affected.

What it is: CVE-2026-35353 is a low-severity vulnerability in Uutils coreutils, published on 22 Apr 2026. 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-2026-35353 in the wild and no public exploit code.

Affected packages and fixed versions:
- uu_mkdir (crates.io): affected all versions; fixed in 0.6.0
- uu_mkdir (crates.io): affected all versions; fixed in 0.6.0

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-2026-35353/ (Markdown: https://insights.sbomify.com/CVE-2026-35353/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-35353
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35353
- OSV: https://osv.dev/vulnerability/CVE-2026-35353

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-35353/
Summaries are generated and may contain mistakes; the official description above is the record.