CVE Catalog

CVE-2026-71250

MediumCVSS 4.3
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.22%

12th percentile - higher than 12% of all known CVEs

Summary

Firefly III's webhook URL validator (IsValidWebhookUrl.php) filters most private/reserved IPv4 ranges but contains an explicit early-return that allows any resolved address in 127.0.0.0/8, permitting an authenticated user (with webhooks enabled, which is off by default) to configure a webhook targeting loopback services on the server.

Risk Assessment

An authenticated user could exploit this vulnerability to attack internal services on the server, potentially leading to unauthorized access or privilege escalation.

Recommendation

It is recommended to extend URL validation to block addresses in the 127.0.0.0/8 range and other internal addresses.

Related vulnerabilities

Original NVD description (English source)

Firefly III's webhook URL validator (IsValidWebhookUrl.php) filters most private/reserved IPv4 ranges but contains an explicit early-return that allows any resolved address in 127.0.0.0/8, permitting an authenticated user (with webhooks enabled, which is off by default) to configure a webhook targeting loopback services on the server.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS