# CVE-2026-35359: uutils coreutils cp Information Disclosure via Time-of-Check to Time-of-Use Symlink Swap

> An attacker can exploit a race condition in the cp utility to copy sensitive files by swapping a regular file with a symlink during execution.

- **Severity:** Medium 4.7 (`CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/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-2026-35359, GHSA-hpfw-mqm3-33jh, UBUNTU-CVE-2026-35359

## What is CVE-2026-35359?

CVE-2026-35359 is a medium-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

A Time-of-Check to Time-of-Use (TOCTOU) vulnerability in the cp utility of uutils coreutils allows an attacker to bypass no-dereference intent. The utility checks if a source path is a symbolic link using path-based metadata but subsequently opens it without the O_NOFOLLOW flag. An attacker with concurrent write access can swap a regular file for a symbolic link during this window, causing a privileged cp process to copy the contents of arbitrary sensitive files into a destination controlled by the attacker.

Weakness: CWE-59 (Improper Link Resolution Before File Access), CWE-367 (Time-of-check Time-of-use (TOCTOU) Race Condition)

## Which versions are affected by CVE-2026-35359?

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


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `coreutils` | crates.io | All versions to 0.8.0 | None |
| `coreutils` | crates.io | All versions to 0.8.0 | None |

Products: Uutils Coreutils.

## How do I fix CVE-2026-35359?

Apply the vendor's patch.

## Is CVE-2026-35359 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35359 exists.

## 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-2026-35359 and fix it if it is affected.

What it is: CVE-2026-35359 is a medium-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: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-35359 exists.

Affected packages and fixed versions:
- coreutils (crates.io): affected all versions up to 0.8.0; no fix listed
- coreutils (crates.io): affected all versions up to 0.8.0; no fix listed

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-2026-35359/ (Markdown: https://insights.sbomify.com/CVE-2026-35359/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-35359
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-35359
- OSV: https://osv.dev/vulnerability/CVE-2026-35359

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-35359/
Summaries are generated and may contain mistakes; the official description above is the record.