# CVE-2018-8373: Microsoft Scripting Engine Memory Corruption

> Remote attackers can execute arbitrary code via memory corruption in the Internet Explorer scripting engine.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Yes, since 25 Mar 2022 (CISA KEV)
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 15 Aug 2018
- **Updated:** 21 Oct 2025
- **Also known as:** GHSA-9qm8-3m9q-ghgq

## What is CVE-2018-8373?

CVE-2018-8373 is a high-severity memory corruption vulnerability in Microsoft Internet Explorer, published on 15 Aug 2018. 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

A remote code execution vulnerability exists in the way that the scripting engine handles objects in memory in Internet Explorer, aka "Scripting Engine Memory Corruption Vulnerability." This affects Internet Explorer 9, Internet Explorer 11, Internet Explorer 10. This CVE ID is unique from CVE-2018-8353, CVE-2018-8355, CVE-2018-8359, CVE-2018-8371, CVE-2018-8372, CVE-2018-8385, CVE-2018-8389, CVE-2018-8390.

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

## Which versions are affected by CVE-2018-8373?

It affects 1 product.


Products: Microsoft Internet Explorer.

## How do I fix CVE-2018-8373?

No fix has been published for CVE-2018-8373 yet. Limit exposure of the affected software until one is available. US federal agencies must fix it by 15 Apr 2022.

## Is CVE-2018-8373 being exploited?

Yes. Attackers have exploited CVE-2018-8373 in the wild since at least 25 Mar 2022.

## Other vulnerabilities in Microsoft Internet Explorer

- [CVE-2014-1776](https://insights.sbomify.com/CVE-2014-1776/): Microsoft Internet Explorer Memory Corruption (critical 9.8, exploited in the wild)
- [CVE-2021-27085](https://insights.sbomify.com/CVE-2021-27085/): Microsoft Internet Explorer Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2017-0222](https://insights.sbomify.com/CVE-2017-0222/): Microsoft Internet Explorer Remote Code Execution (high 8.8, exploited in the wild)
- [CVE-2017-0210](https://insights.sbomify.com/CVE-2017-0210/): Microsoft Internet Explorer Privilege Escalation (high 8.8, exploited in the wild)
- [CVE-2017-0149](https://insights.sbomify.com/CVE-2017-0149/): Microsoft Internet Explorer Memory Corruption (high 8.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2018-8373 and fix it if it is affected.

What it is: CVE-2018-8373 is a high-severity memory corruption vulnerability in Microsoft Internet Explorer, published on 15 Aug 2018. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Exploitation: Yes. Attackers have exploited CVE-2018-8373 in the wild since at least 25 Mar 2022.

Affected product: Microsoft Internet Explorer. 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-2018-8373/ (Markdown: https://insights.sbomify.com/CVE-2018-8373/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2018-8373
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2018-8373
- OSV: https://osv.dev/vulnerability/CVE-2018-8373

---
From sbomify Insights: https://insights.sbomify.com/CVE-2018-8373/
Summaries are generated and may contain mistakes; the official description above is the record.