CVE-2026-46348
HighCVSS 8.7Exploitation Probability (EPSS)
Low risk26th percentile — higher than 26% of all known CVEs
Summary
Mastodon, a social network server based on ActivityPub, prior to versions 4.5.10, 4.4.17, and 4.3.23, had a vulnerability in the list of disallowed IP address ranges, allowing attackers to make HTTP requests to loopback interfaces. This could lead to unauthorized access to private resources and services.
Risk Assessment
Organizations using Mastodon may be exposed to unauthorized access to internal resources, potentially leading to data leaks or other serious security incidents.
Recommendation
It is recommended to update Mastodon to versions 4.5.10, 4.4.17, or 4.3.23 to eliminate this vulnerability and secure the system against potential attacks.
Original NVD description (English source)
Mastodon is a free, open-source social network server based on ActivityPub. Prior to 4.5.10, 4.4.17, and 4.3.23, the list of disallowed IP address ranges was lacking an IP address range that can be used to reach local IP addresses. An attacker can use an IP address in the affected range to make Mastodon perform HTTP requests against loopback interfaces, potentially allowing access to otherwise private resources and services. This vulnerability is fixed in 4.5.10, 4.4.17, and 4.3.23.