# CVE-2025-43421: Memory corruption in Safari

> Processing malicious web content causes an unexpected process crash in Apple Safari and related operating systems.

- **Severity:** Medium 4.3 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 4 Nov 2025
- **Updated:** 2 Apr 2026
- **Also known as:** DEBIAN-CVE-2025-43421, GHSA-43xx-j7mw-696v, UBUNTU-CVE-2025-43421

## What is CVE-2025-43421?

CVE-2025-43421 is a medium-severity memory corruption vulnerability in Apple Ipados, published on 4 Nov 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

### Official description

Multiple issues were addressed by disabling array allocation sinking. This issue is fixed in Safari 26.1, iOS 26.1 and iPadOS 26.1, macOS Tahoe 26.1, visionOS 26.1. Processing maliciously crafted web content may lead to an unexpected process crash.

Weakness: CWE-787 (Out-of-bounds Write), CWE-125 (Out-of-bounds Read)

## Which versions are affected by CVE-2025-43421?

It affects 4 products.


Products: Apple Ipados, Apple Iphone Os, Apple Safari, Apple Visionos.

## How do I fix CVE-2025-43421?

Upgrade to a fixed version.

## Is CVE-2025-43421 being exploited?

There is no known exploitation of CVE-2025-43421 in the wild and no public exploit code.

## Other vulnerabilities in Apple Ipados

- [CVE-2025-43300](https://insights.sbomify.com/CVE-2025-43300/): Apple iOS, iPadOS, and macOS Out-of-Bounds Write (critical 10.0, exploited in the wild)
- [CVE-2025-24201](https://insights.sbomify.com/CVE-2025-24201/): Apple Multiple Products WebKit Out-of-Bounds Write (critical 10.0, exploited in the wild)
- [CVE-2025-24085](https://insights.sbomify.com/CVE-2025-24085/): Apple Multiple Products Use-After-Free (critical 10.0, exploited in the wild)
- [CVE-2025-31200](https://insights.sbomify.com/CVE-2025-31200/): Apple Multiple Products Memory Corruption (critical 9.8, exploited in the wild)
- [CVE-2025-31201](https://insights.sbomify.com/CVE-2025-31201/): Apple Multiple Products Arbitrary Read and Write (critical 9.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-43421 and fix it if it is affected.

What it is: CVE-2025-43421 is a medium-severity memory corruption vulnerability in Apple Ipados, published on 4 Nov 2025. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2025-43421 in the wild and no public exploit code.

Affected product: Apple Ipados. 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-2025-43421/ (Markdown: https://insights.sbomify.com/CVE-2025-43421/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-43421
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-43421
- OSV: https://osv.dev/vulnerability/CVE-2025-43421

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-43421/
Summaries are generated and may contain mistakes; the official description above is the record.