# CVE-2024-39891

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.)

- Page: https://www.vulneraibility.com/cve/CVE-2024-39891
- CVSS: 5.3
- Known exploited: yes, in CISA KEV since 2024-07-23; CISA due date 2024-08-13
- EPSS: 1.67% (percentile 77.1)
- CISA SSVC: exploitation active, automatable yes, technical impact partial (assessed 2024-07-23)
- Weakness: CWE-203
- Published: 2024-07-02

## Affected

- twilio:authy
- twilio:authy_authenticator

## References

- [other] https://cwe.mitre.org/data/definitions/203.html
- [other] https://www.twilio.com/docs/usage/security/reporting-vulnerabilities
- [other] https://www.twilio.com/en-us/changelog
- [other] https://www.bleepingcomputer.com/news/security/hackers-abused-api-to-verify-millions-of-authy-mfa-phone-numbers/
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-39891

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.