# CVE-2020-3864: Security feature bypass in Safari

> Attackers can bypass same-origin policy restrictions in Safari and related Apple services due to a DOM object context validation flaw.

- **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:** 27 Oct 2020
- **Updated:** 4 Aug 2024
- **Also known as:** DEBIAN-CVE-2020-3864, GHSA-wwr3-9qhx-q62f, UBUNTU-CVE-2020-3864

## What is CVE-2020-3864?

CVE-2020-3864 is a high-severity vulnerability in Apple Icloud, published on 27 Oct 2020. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

A logic issue was addressed with improved validation. This issue is fixed in iCloud for Windows 7.17, iTunes 12.10.4 for Windows, iCloud for Windows 10.9.2, tvOS 13.3.1, Safari 13.0.5, iOS 13.3.1 and iPadOS 13.3.1. A DOM object context may not have had a unique security origin.

Weakness: CWE-346 (Origin Validation Error)

## Which versions are affected by CVE-2020-3864?

It affects 9 products.


Products: Apple Icloud, Apple Ipados, Apple Iphone Os, Apple Itunes, Apple Safari, Apple Tvos, Redhat Enterprise Linux Desktop, Redhat Enterprise Linux Server, Redhat Enterprise Linux Workstation.

## How do I fix CVE-2020-3864?

Upgrade to a fixed version.

## Is CVE-2020-3864 being exploited?

There is no known exploitation of CVE-2020-3864 in the wild and no public exploit code.

## Other vulnerabilities in Apple Icloud

- [CVE-2019-8506](https://insights.sbomify.com/CVE-2019-8506/): Apple Multiple Products Type Confusion (high 8.8, exploited in the wild)
- [CVE-2020-27932](https://insights.sbomify.com/CVE-2020-27932/): Apple Multiple Products Type Confusion (high 7.8, exploited in the wild)
- [CVE-2019-8746](https://insights.sbomify.com/CVE-2019-8746/): Memory corruption in iOS (critical 9.8)
- [CVE-2019-8749](https://insights.sbomify.com/CVE-2019-8749/): Memory corruption in iOS (critical 9.8)
- [CVE-2019-8756](https://insights.sbomify.com/CVE-2019-8756/): Memory corruption in iOS (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-3864 and fix it if it is affected.

What it is: CVE-2020-3864 is a high-severity vulnerability in Apple Icloud, published on 27 Oct 2020. 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-2020-3864 in the wild and no public exploit code.

Affected product: Apple Icloud. 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-2020-3864/ (Markdown: https://insights.sbomify.com/CVE-2020-3864/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-3864
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-3864
- OSV: https://osv.dev/vulnerability/CVE-2020-3864

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-3864/
Summaries are generated and may contain mistakes; the official description above is the record.