# CVE-2026-65986: CVAT has stored XSS via annotation guide assets

> Attackers can execute arbitrary JavaScript in victims' browsers by uploading malicious annotation guide assets with manipulated content types.

- **Severity:** High 8.5 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:H/VI:H/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:** 4 Aug 2026
- **Updated:** 5 Aug 2026
- **Also known as:** GHSA-w6mx-95ff-72cv

## What is CVE-2026-65986?

CVE-2026-65986 is a high-severity cross-site scripting vulnerability in cvat-ai cvat, published on 4 Aug 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

CVAT is an open source interactive video and image annotation tool for computer vision. Versions 2.5.0 through 2.66.0 contain a XSS vulnerability that can be accessed through annotation guide assets. When CVAT serves the files attached to an annotation guide, it labels them with a media type ( Content-Type ) that the attacker can influence, so instead of treating an uploaded file as plain data, the victim's browser can be told to treat it as an HTML page and run any JavaScript inside it. This issue has been fixed in version 2.67.0.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation), CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2026-65986?


## How do I fix CVE-2026-65986?

No fix has been published for CVE-2026-65986 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-65986 being exploited?

There is no known exploitation of CVE-2026-65986 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-65986 and fix it if it is affected.

What it is: CVE-2026-65986 is a high-severity cross-site scripting vulnerability in cvat-ai cvat, published on 4 Aug 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-2026-65986 in the wild and no public exploit code.

Affected product: cvat-ai cvat. 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-2026-65986/ (Markdown: https://insights.sbomify.com/CVE-2026-65986/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-65986
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-65986
- OSV: https://osv.dev/vulnerability/CVE-2026-65986

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-65986/
Summaries are generated and may contain mistakes; the official description above is the record.