# CVE-2025-9824: User Enumeration via Response Timing

> Attackers can enumerate valid usernames by analyzing login response timing differences, facilitating subsequent brute-force attacks.

- **Severity:** Medium 5.9 (`CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 3 Sep 2025
- **Updated:** 3 Sep 2025
- **Also known as:** GHSA-3ggv-qwcp-j6xg

## What is CVE-2025-9824?

CVE-2025-9824 is a medium-severity vulnerability in Mautic, published on 3 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

ImpactThe attacker can validate if a user exists by checking the time login returns. This timing difference can be used to enumerate valid usernames, after which an attacker could attempt brute force attacks.

PatchesThis vulnerability has been patched, implementing a timing-safe form login authenticator that ensures consistent response times regardless of whether a user exists or not.

Technical DetailsThe vulnerability was caused by different response times when:

  *  A valid username was provided (password hashing occurred)
  *  An invalid username was provided (no password hashing occurred)

The fix introduces a TimingSafeFormLoginAuthenticator that performs a dummy password hash verification even for non-existent users, ensuring consistent timing.

WorkaroundsNo workarounds are available. Users should upgrade to the patched version.

References  *   https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/03-Identity_Management_Testing/04-Testing_for_Account_Enumeration_and_Guessable_User_Account

Weakness: CWE-204 (Observable Response Discrepancy)

## Which versions are affected by CVE-2025-9824?

6 open source packages ship an affected version, including mautic/core.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `mautic/core` | Packagist | From 4.4.0 | 4.4.17 |
| `mautic/core` | Packagist | From 4.4.0 | 4.4.17 |
| `mautic/core` | Packagist | From 5.0.0-alpha | 5.2.8 |
| `mautic/core` | Packagist | From 5.0.0-alpha | 5.2.8 |
| `mautic/core` | Packagist | From 6.0.0-alpha | 6.0.5 |
| `mautic/core` | Packagist | From 6.0.0-alpha | 6.0.5 |

## How do I fix CVE-2025-9824?

Upgrade mautic/core to a fixed version for your release line: 4.4.17, 5.2.8 or 6.0.5.

## Is CVE-2025-9824 being exploited?

There is no known exploitation of CVE-2025-9824 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2025-9824 and fix it if it is affected.

What it is: CVE-2025-9824 is a medium-severity vulnerability in Mautic, published on 3 Sep 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2025-9824 in the wild and no public exploit code.

Affected packages and fixed versions:
- mautic/core (Packagist): affected from 4.4.0; fixed in 4.4.17
- mautic/core (Packagist): affected from 4.4.0; fixed in 4.4.17
- mautic/core (Packagist): affected from 5.0.0-alpha; fixed in 5.2.8
- mautic/core (Packagist): affected from 5.0.0-alpha; fixed in 5.2.8
- mautic/core (Packagist): affected from 6.0.0-alpha; fixed in 6.0.5
- mautic/core (Packagist): affected from 6.0.0-alpha; fixed in 6.0.5

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-2025-9824/ (Markdown: https://insights.sbomify.com/CVE-2025-9824/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2025-9824
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2025-9824
- OSV: https://osv.dev/vulnerability/CVE-2025-9824

---
From sbomify Insights: https://insights.sbomify.com/CVE-2025-9824/
Summaries are generated and may contain mistakes; the official description above is the record.