CVE-2025-9821 SSRF via webhook function
Users with webhook permissions can perform Server-Side Request Forgery to access internal services and potentially view partial response data.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2025-9821?
CVE-2025-9821 is a low-severity server-side request forgery vulnerability in Mautic, published on 3 Sep 2025. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
SummaryUsers with webhook permissions can conduct SSRF via webhooks. If they have permission to view the webhook logs, the (partial) request response is also disclosed
DetailsWhen sending webhooks, the destination is not validated, causing SSRF.
ImpactBypass of firewalls to interact with internal services. See https://owasp.org/Top10/A10_2021-Server-Side_Request_Forgery_%28SSRF%29/ for more potential impact.
Resources https://cheatsheetseries.owasp.org/cheatsheets/Server_Side_Request_Forgery_Prevention_Cheat_Sheet.html for more information on SSRF and its fix.
Weakness: CWE-918
Which versions are affected by CVE-2025-9821?
6 open source packages ship an affected version, including mautic/core.
| Package | 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-2025-9821?
Upgrade mautic/core to a fixed version for your release line: 4.4.17, 5.2.8 or 6.0.5.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2025-9821 being exploited?
There is no known exploitation of CVE-2025-9821 in the wild and no public exploit code.
Sources
Also known as GHSA-hj6f-7hp7-xg69.