# CVE-2026-61448: Parse Server 9.0.0 Stored XSS via malformed Content-Type

> Attackers can execute arbitrary scripts in other users' browsers by uploading files with malformed Content-Type headers when using specific cloud storage adapters.

- **Severity:** Low 2.1 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:P/VC:N/VI:L/VA:N/SC:L/SI:L/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** Yes
- **Published:** 11 Jul 2026
- **Updated:** 14 Jul 2026
- **Also known as:** BIT-parse-2026-61448, GHSA-r899-h629-j84r

## What is CVE-2026-61448?

CVE-2026-61448 is a low-severity cross-site scripting vulnerability in parse-community parse-server, published on 11 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Parse Server is affected by a stored cross-site scripting (XSS) vulnerability in versions >= 9.0.0, < 9.10.0-alpha.2 and <= 8.6.83. When an uploaded file's extension is not recognized by the mime package, Parse Server preserves the client-supplied Content-Type. A malformed Content-Type that is not a valid type/subtype media type (e.g., 'image', 'image/', or 'image//svg+xml') bypasses the fileUpload.fileExtensions blocklist and is stored unchanged. On storage adapters that persist and serve the uploaded Content-Type (such as Amazon S3, Google Cloud Storage, or Azure Blob Storage), a browser cannot parse the malformed value and falls back to MIME-sniffing; a file whose body begins with HTML is rendered as HTML, executing embedded script in the application's origin against other users who open the file URL. The default GridFS storage adapter is not affected. Fixed in 9.10.0-alpha.2 and 8.6.84.

Weakness: CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2026-61448?

5 open source packages ship an affected version, including parse-server and parse.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `parse-server` | npm | All versions | 8.6.84 |
| `parse-server` | npm | All versions | 8.6.84 |
| `parse-server` | npm | From 9.0.0 | 9.10.0-alpha.2 |
| `parse-server` | npm | From 9.0.0 | 9.10.0-alpha.2 |
| `parse` | Bitnami | All versions | 8.6.84, 9.10.0 |

## How do I fix CVE-2026-61448?

Upgrade parse-server to a fixed version for your release line: 8.6.84 or 9.10.0-alpha.2.

## Is CVE-2026-61448 being exploited?

There is no known exploitation of CVE-2026-61448 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-61448 and fix it if it is affected.

What it is: CVE-2026-61448 is a low-severity cross-site scripting vulnerability in parse-community parse-server, published on 11 Jul 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-61448 in the wild and no public exploit code.

Affected packages and fixed versions:
- parse-server (npm): affected all versions; fixed in 8.6.84
- parse-server (npm): affected all versions; fixed in 8.6.84
- parse-server (npm): affected from 9.0.0; fixed in 9.10.0-alpha.2
- parse-server (npm): affected from 9.0.0; fixed in 9.10.0-alpha.2
- parse (Bitnami): affected all versions; fixed in 8.6.84, 9.10.0

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-2026-61448/ (Markdown: https://insights.sbomify.com/CVE-2026-61448/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-61448
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-61448
- OSV: https://osv.dev/vulnerability/CVE-2026-61448

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-61448/
Summaries are generated and may contain mistakes; the official description above is the record.