# CVE-2026-53595: FreeScout vulnerable to anonymous account takeover via /user-setup empty invite_hash on MySQL

> An anonymous attacker can take over the lowest-ID activated user account in FreeScout by exploiting MySQL string comparison flaws in the user setup endpoint.

- **Severity:** Critical 9.4 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 20 Jul 2026
- **Updated:** 21 Jul 2026
- **Also known as:** GHSA-jqj5-r72v-v29g

## What is CVE-2026-53595?

CVE-2026-53595 is a critical authentication bypass vulnerability in freescout-help-desk freescout, published on 20 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.224, the public endpoint `POST /user-setup/{hash}/{invite_sent_at}` (`OpenController@userSetupSave`) selects the target account solely by its `invite_hash` column, then overwrites that account's email and password and logs in as it. No authentication, cookie, or prior session is required. After a user activates, FreeScout sets `invite_hash` to the empty string. On MySQL and MariaDB, `VARCHAR` equality ignores trailing spaces, so a single URL-encoded space (`%20`) matches the stored empty string and selects the lowest-id activated user. The expiry guard decrypts `invite_sent_at` with the target's password hash, but `Helper::decrypt` returns its raw input unchanged when decryption fails. A plaintext numeric value such as `9999999999` therefore passes the time-to-live check without any secret. The result is that an anonymous attacker sets the email and password of the lowest-id activated FreeScout account (a support agent, or an administrator if one was added by invitation) and authenticates as that account. Version 1.8.224 contains a fix.

Weakness: CWE-640 (Weak Password Recovery Mechanism for Forgotten Password), CWE-287 (Improper Authentication), CWE-178 (Improper Handling of Case Sensitivity)

## Which versions are affected by CVE-2026-53595?


## How do I fix CVE-2026-53595?

No fix has been published for CVE-2026-53595 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-53595 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-53595 exists.

Public exploit code:

- https://github.com/0xdak/CVE-2026-53595_exploit (github_poc): https://github.com/0xdak/CVE-2026-53595_exploit
- FreeScout < 1.8.224 - Invite Hash Authorization Bypass (nuclei): http/cves/2026/CVE-2026-53595.yaml

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-53595 and fix it if it is affected.

What it is: CVE-2026-53595 is a critical authentication bypass vulnerability in freescout-help-desk freescout, published on 20 Jul 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-2026-53595 exists.

Affected product: freescout-help-desk freescout. 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-2026-53595/ (Markdown: https://insights.sbomify.com/CVE-2026-53595/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-53595
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-53595
- OSV: https://osv.dev/vulnerability/CVE-2026-53595

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From sbomify Insights: https://insights.sbomify.com/CVE-2026-53595/
Summaries are generated and may contain mistakes; the official description above is the record.