# CVE-2019-0548: Denial of service in ASP.NET Core

> Attackers can cause a denial of service in ASP.NET Core by sending improperly handled web requests, affecting service availability.

- **Severity:** High 7.5 (`CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 8 Jan 2019
- **Updated:** 4 Aug 2024
- **Also known as:** GHSA-9pfr-cc3p-p98q

## What is CVE-2019-0548?

CVE-2019-0548 is a high-severity denial of service vulnerability in Microsoft ASP.NET Core, published on 8 Jan 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A denial of service vulnerability exists when ASP.NET Core improperly handles web requests, aka "ASP.NET Core Denial of Service Vulnerability." This affects ASP.NET Core 2.2, ASP.NET Core 2.1. This CVE ID is unique from CVE-2019-0564.

Weakness: CWE-19

## Which versions are affected by CVE-2019-0548?

It affects 1 product.


Products: Microsoft Asp.net Core.

## How do I fix CVE-2019-0548?

Apply the vendor's patch.

## Is CVE-2019-0548 being exploited?

There is no known exploitation of CVE-2019-0548 in the wild and no public exploit code.

## Other vulnerabilities in Microsoft ASP.NET Core

- [CVE-2025-55315](https://insights.sbomify.com/CVE-2025-55315/): ASP.NET Security Feature Bypass Vulnerability (critical 9.9)
- [CVE-2026-88092](https://insights.sbomify.com/CVE-2026-88092/): ASP.NET Core Tampering Vulnerability (critical 9.4)
- [CVE-2026-40372](https://insights.sbomify.com/CVE-2026-40372/): ASP.NET Core Elevation of Privilege Vulnerability (critical 9.1)
- [CVE-2021-43877](https://insights.sbomify.com/CVE-2021-43877/): ASP.NET Core and Visual Studio Elevation of Privilege Vulnerability (high 8.8)
- [CVE-2020-0603](https://insights.sbomify.com/CVE-2020-0603/): Remote code execution in ASP.NET Core (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2019-0548 and fix it if it is affected.

What it is: CVE-2019-0548 is a high-severity denial of service vulnerability in Microsoft ASP.NET Core, published on 8 Jan 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2019-0548 in the wild and no public exploit code.

Affected product: Microsoft ASP.NET Core. 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-2019-0548/ (Markdown: https://insights.sbomify.com/CVE-2019-0548/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2019-0548
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2019-0548
- OSV: https://osv.dev/vulnerability/CVE-2019-0548

---
From sbomify Insights: https://insights.sbomify.com/CVE-2019-0548/
Summaries are generated and may contain mistakes; the official description above is the record.