CVE-2025-9821
LOWCVE-2025-9821 is a low-severity (CVSS 2.7) Server-Side Request Forgery (SSRF) vulnerability in mautic/core. O3 Security confirms whether CVE-2025-9821 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SSRF via webhook function
Real-World Exposure
mautic/core🐘mautic/core🐘mautic/coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | mautic/core | ≥ 4.4.0&&< 4.4.17 | 4.4.17 |
| 🐘Packagist | mautic/core | ≥ 5.0.0-alpha&&< 5.2.8 | 5.2.8 |
| 🐘Packagist | mautic/core | ≥ 6.0.0-alpha&&< 6.0.5 | 6.0.5 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mautic/core. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update mautic/core to 4.4.17 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-9821 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-9821 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-9821. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-9821 in your dependencies?
O3 detects CVE-2025-9821 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.