# CVE-2021-30780: Memory corruption in Security Update - Catalina

> A malicious application can exploit an out-of-bounds write to gain root privileges on Apple operating systems.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 8 Sep 2021
- **Updated:** 3 Aug 2024
- **Also known as:** GHSA-6mq7-ggq4-5r36

## What is CVE-2021-30780?

CVE-2021-30780 is a high-severity memory corruption vulnerability in Apple Iphone Os, published on 8 Sep 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

An out-of-bounds write issue was addressed with improved bounds checking. This issue is fixed in iOS 14.7, macOS Big Sur 11.5, watchOS 7.6, tvOS 14.7, Security Update 2021-005 Mojave, Security Update 2021-004 Catalina. A malicious application may be able to gain root privileges.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2021-30780?

It affects 5 products.


Products: Apple Iphone Os, Apple Mac Os X, Apple Macos, Apple Tvos, Apple Watchos.

## How do I fix CVE-2021-30780?

No fix has been published for CVE-2021-30780 yet. Limit exposure of the affected software until one is available.

## Is CVE-2021-30780 being exploited?

There is no known exploitation of CVE-2021-30780 in the wild and no public exploit code.

## Other vulnerabilities in Apple Iphone Os

- [CVE-2021-30666](https://insights.sbomify.com/CVE-2021-30666/): Apple iOS WebKit Buffer Overflow (high 8.8, exploited in the wild)
- [CVE-2021-30761](https://insights.sbomify.com/CVE-2021-30761/): Apple iOS WebKit Memory Corruption (high 8.8, exploited in the wild)
- [CVE-2021-30762](https://insights.sbomify.com/CVE-2021-30762/): Apple iOS WebKit Use-After-Free (high 8.8, exploited in the wild)
- [CVE-2016-4657](https://insights.sbomify.com/CVE-2016-4657/): Apple iOS Webkit Memory Corruption (high 8.8, exploited in the wild)
- [CVE-2019-7286](https://insights.sbomify.com/CVE-2019-7286/): Apple Multiple Products Memory Corruption (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2021-30780 and fix it if it is affected.

What it is: CVE-2021-30780 is a high-severity memory corruption vulnerability in Apple Iphone Os, published on 8 Sep 2021. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2021-30780 in the wild and no public exploit code.

Affected product: Apple Iphone Os. 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-2021-30780/ (Markdown: https://insights.sbomify.com/CVE-2021-30780/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2021-30780
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2021-30780
- OSV: https://osv.dev/vulnerability/CVE-2021-30780

---
From sbomify Insights: https://insights.sbomify.com/CVE-2021-30780/
Summaries are generated and may contain mistakes; the official description above is the record.