EXPOSURES › CVE-2024-39891
CVE-2024-39891
HIGH ⌖ ON CISA KEV · EXPLOITEDTwilio Authy API disclosed whether a phone number was registered without authentication, enabling reconnaissance for credential harvesting.
An unauthenticated endpoint in Twilio Authy's API revealed whether a phone number was registered, allowing attackers to map user accounts before credential theft. This reconnaissance capability aids adversaries in targeting high-value accounts, increasing the risk of data breaches and compromising FedRAMP vendor trust.
Shame score — The vulnerability was disclosed responsibly and does not allow direct data exfiltration, though it enables reconnaissance.
▸ RECOMMENDED ACTION Actively exploited (CISA KEV) — remediate now, ahead of your normal patch cycle.
Twilio Authy contains an information disclosure vulnerability in its API that allows an unauthenticated endpoint to accept a request containing a phone number and respond with information about whether the phone number was registered with Authy.