An issue was discovered on AudioCodes Mediant 500L-MSBR, 500-MBSR, M800B-MSBR and 800C-MSBR devices with firmware versions before 7.20A.202.307. A Cross-Site Request Forgery (CSRF) vulnerability in the management web interface allows remote attackers to execute malicious and unauthorized actions, because CSRFProtection=1 is not a default and is not documented.