Actively exploited · Published Jul 2, 2024 · Assigned by mitre
CVE-2024-39891
Medium 5.3 Exploited
In plain English
A medium-severity security flaw in Authy from Twilio. Attackers are actively exploiting it in the wild (listed by CISA on July 23, 2024). The chance it is exploited in the next 30 days is estimated at 1.7% (higher than 77% of all known vulnerabilities). Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
CISA guidance
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Federal agencies must remediate by Aug 13, 2024.
Official description
In the Twilio Authy API, accessed by Authy Android before 25.1.0 and Authy iOS before 26.1.0, an unauthenticated endpoint provided access to certain phone-number data, as exploited in the wild in June 2024. Specifically, the endpoint accepted a stream of requests containing phone numbers, and responded with information about whether each phone number was registered with Authy. (Authy accounts were not compromised, however.)
Affected products (as reported)
Weakness: CWE-203 · Vector: CVSS:3.1/AC:L/AV:N/A:N/C:L/I:N/PR:N/S:U/UI:N
References
- https://cwe.mitre.org/data/definitions/203.html
- https://www.twilio.com/docs/usage/security/reporting-vulnerabilities
- https://www.twilio.com/en-us/changelog
- https://www.bleepingcomputer.com/news/security/hackers-abused-api-to-verify-millions-of-authy-mfa-phone-numbers/
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-39891 government-resource