---
title: "CVE-2020-8252\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2020-8252?format=md
keywords: index, follow
---

# CVE-2020-8252

Publication date 18 September 2020

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2020-8252?format=md#impact-score)

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## Description

The implementation of realpath in libuv < 10.22.1, < 12.18.4, and < 14.9.0
used within Node.js incorrectly determined the buffer size which can result
in a buffer overflow if the resolved path is longer than 256 bytes.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2020-8252?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| libuv1 | 20.04 LTS focal | Fixed 1.34.2-1ubuntu1.1 |
| 18.04 LTS bionic | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2020-8252?format=md#patch-details)

## Notes

---

### [sbeattie](https://launchpad.net/~sbeattie)

nodejs uses system libuv1 library

---

### [mdeslaur](https://launchpad.net/~mdeslaur)

introduced in 1.24.0

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| libuv1 | * Upstream:   [0e6e862](https://github.com/libuv/libuv/commit/0e6e8620496dff0eb285589ef1e37a7f407f3ddd) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.8 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.8 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-8252)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2020-8252)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2020-8252)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2020-8252)

### Related Ubuntu Security Notices (USN)

+ [USN-4548-1](https://usn.ubuntu.com/USN-4548-1)
+ libuv vulnerability
+ 28 September 2020

### Other references

* <https://hackerone.com/reports/965914>
* <https://nodejs.org/en/blog/vulnerability/september-2020-security-releases/#fs-realpath-native-on-may-cause-buffer-overflow-medium-cve-2020-8252>
* <https://nodejs.org/en/blog/vulnerability/september-2020-security-releases/>
* <https://www.cve.org/CVERecord?id=CVE-2020-8252>