CVE-2025-66482 - Misskey has a login rate limit bypass via spoofed X-Forwarded-For header

CVE ID : CVE-2025-66482 Published : 15 Dec 2025, 11:18 p.m. | 18 minutes ago Description : Misskey is an open source, federated social media platform. Attackers who use an untrusted reverse proxy or not using a reverse proxy at all can bypass IP rate limiting by adding a forged X-Forwarded-For header. Starting with version 2025.9.1, an option (`trustProxy`) has been added in config file to prevent this from happening. However, it is initialized with an insecure default value before version 2025.12.0-alpha.2, making it still vulnerable if the configuration is not set correctly. This is patched in v2025.12.0-alpha.2 by flipping default value of `trustProxy` to `false`. Users of a trusted reverse proxy who are unsure if they manually overode this value should check their config for optimal behavior. Users are running Misskey with a trusted reverse proxy should not be affected by this vulnerability. From v2025.9.1 to v2025.11.1, workaround is available. Set `trustProxy: false` in config file. Severity: 0.0 | NA Visit the link for more details, such as CVSS details, affected products, timeline, and more...

Source: Telegram CVE Monitor