# CVE-2025-66803: Turbo Frame responses can restore stale session cookies

> Remote attackers can bypass logout mechanisms by exploiting a race condition in Hotwired Turbo, allowing session cookies to be reapplied after logout.

- **Severity:** Medium 4.8 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 20 Jan 2026
- **Updated:** 21 Jan 2026
- **Also known as:** GHSA-qppm-g56g-fpvp

## What is CVE-2025-66803?

CVE-2025-66803 is a medium-severity vulnerability in n/a, published on 20 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Race condition in the turbo-frame element handler in Hotwired Turbo before 8.0.x causes logout operations to fail when delayed frame responses reapply session cookies after logout. This can be exploited by remote attackers via selective network delays (e.g. delaying requests based on sequence or timing) or by physically proximate attackers when the race condition occurs naturally on shared computers.

Weakness: CWE-362 (Concurrent Execution using Shared Resource with Improper Synchronization)

## Which versions are affected by CVE-2025-66803?

2 open source packages ship an affected version, including @hotwired/turbo. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@hotwired/turbo` | npm | All versions | 8.0.21 |
| `@hotwired/turbo` | npm | All versions | 8.0.21 |

Products: Hotwired Turbo.

## How do I fix CVE-2025-66803?

Upgrade @hotwired/turbo to 8.0.21 or later.

## Is CVE-2025-66803 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66803 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-66803 and fix it if it is affected.

What it is: CVE-2025-66803 is a medium-severity vulnerability in n/a, published on 20 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2025-66803 exists.

Affected packages and fixed versions:
- @hotwired/turbo (npm): affected all versions; fixed in 8.0.21
- @hotwired/turbo (npm): affected all versions; fixed in 8.0.21

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-2025-66803/ (Markdown: https://insights.sbomify.com/CVE-2025-66803/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-66803
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-66803
- OSV: https://osv.dev/vulnerability/CVE-2025-66803

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-66803/
Summaries are generated and may contain mistakes; the official description above is the record.