Nitter's /video media proxy endpoint fails to validate target URLs against Twitter/X domains and uses a hardcoded default HMAC key, allowing unauthenticated attackers to compute valid HMACs for arbitrary URLs. Attackers can retrieve HTTP responses from any host reachable by the server, including cloud metadata services and internal network resources.
Exploitability
AV:NAC:LAT:NPR:NUI:NVulnerable System
VC:NVI:LVA:NSubsequent System
SC:HSI:NSA:N7.7/CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:NInput Validation
Other