# CVE-2026-5026: Langflow - Stored XSS via Malicious SVG Upload

> Attackers can upload malicious SVG files to execute JavaScript, stealing authentication tokens from other users.

- **Severity:** High 7.0 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:L/VA:N/SC:N/SI:N/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:** No
- **Published:** 27 Mar 2026
- **Updated:** 27 Mar 2026
- **Also known as:** GHSA-89f7-r7x8-83q7

## What is CVE-2026-5026?

CVE-2026-5026 is a high-severity cross-site scripting vulnerability in Langflow Langflow, published on 27 Mar 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

The '/api/v1/files/images/{flow_id}/{file_name}' endpoint serves SVG files with the 'image/svg+xml' content type without sanitizing their content.

Since SVG files can contain embedded JavaScript, an attacker can upload a malicious SVG that executes arbitrary JavaScript when viewed by other users, leading to stored cross-site scripting (XSS). This allows stealing authentication tokens stored in cookies, including JWT access and refresh tokens.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2026-5026?

It affects 1 product.


Products: Langflow Langflow.

## How do I fix CVE-2026-5026?

No fix has been published for CVE-2026-5026 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-5026 being exploited?

There is no known exploitation of CVE-2026-5026 in the wild and no public exploit code.

## Other vulnerabilities in Langflow Langflow

- [CVE-2026-9198](https://insights.sbomify.com/CVE-2026-9198/): IBM Langflow Code Injection (critical 9.8, exploited in the wild)
- [CVE-2026-0770](https://insights.sbomify.com/CVE-2026-0770/): Langflow Inclusion of Functionality from Untrusted Control Sphere (critical 9.8, exploited in the wild)
- [CVE-2025-3248](https://insights.sbomify.com/CVE-2025-3248/): Langflow Missing Authentication (critical 9.8, exploited in the wild)
- [CVE-2025-34291](https://insights.sbomify.com/CVE-2025-34291/): Langflow Origin Validation Error (critical 9.4, exploited in the wild)
- [CVE-2026-33017](https://insights.sbomify.com/CVE-2026-33017/): Langflow Code Injection (critical 9.3, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-5026 and fix it if it is affected.

What it is: CVE-2026-5026 is a high-severity cross-site scripting vulnerability in Langflow Langflow, published on 27 Mar 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-2026-5026 in the wild and no public exploit code.

Affected product: Langflow Langflow. 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-2026-5026/ (Markdown: https://insights.sbomify.com/CVE-2026-5026/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-5026
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-5026
- OSV: https://osv.dev/vulnerability/CVE-2026-5026

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-5026/
Summaries are generated and may contain mistakes; the official description above is the record.