A network man-in-the-middle between nats-sync and the BOSH director can steal the director credentials (Basic auth header or UAA client secret) and can tamper with the VM list that is written into the NATS authorization file. Stolen credentials grant administrative director access. UsersSync#bosh_api_response_body builds a Net::HTTP client with verify_mode = OpenSSL::SSL::VERIFY_NONE for every director call (/info, /deployments, /deployments/<name>/vms).
Affected versions:
Exploitability
AV:LAC:LAT:PPR:LUI:NVulnerable System
VC:HVI:LVA:NSubsequent System
SC:HSI:HSA:H7.1/CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:H/VI:L/VA:N/SC:H/SI:H/SA:HCryptography