# CVE-2024-39891: Twilio Authy Information Disclosure Vulnerability

> CVE-2024-39891: Twilio Authy Information Disclosure Vulnerability. CVSS 5.3 (CVSS 3.1), in CISA KEV.

Canonical: https://rewindex.com/cve/CVE-2024-39891
Last updated: 2025-10-21T22:55:50Z

- Published: 2024-07-02 00:00 UTC · Updated: 2025-10-21 22:55 UTC · Assigner: mitre
- CVSS: 5.3 (CVSS 3.1) · Severity: Medium · Vector: CVSS:3.1/AC:L/AV:N/A:N/C:L/I:N/PR:N/S:U/UI:N
- EPSS: 1.7%, 77th percentile (scored 2026-10-25)
- CISA KEV: yes, added 2024-07-23, federal due date 2024-08-13, ransomware use: Unknown

## 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.)

## CISA required action

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

## Affected vendors and products

- twilio: authy\_2-factor\_authentication

## Tracked companies

- [Twilio](https://rewindex.com/company/twilio.md)

## References

- [CVE record on cve.org](https://www.cve.org/CVERecord?id=CVE-2024-39891)
- [NVD entry](https://nvd.nist.gov/vuln/detail/CVE-2024-39891)
- [https://cwe.mitre.org/data/definitions/203.html](https://cwe.mitre.org/data/definitions/203.html)
- [https://www.bleepingcomputer.com/news/security/hackers-abused-api-to-verify-millions-of-authy-mfa-phone-numbers/](https://www.bleepingcomputer.com/news/security/hackers-abused-api-to-verify-millions-of-authy-mfa-phone-numbers/)
- [https://www.twilio.com/docs/usage/security/reporting-vulnerabilities](https://www.twilio.com/docs/usage/security/reporting-vulnerabilities)
- [https://www.twilio.com/en-us/changelog](https://www.twilio.com/en-us/changelog)

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_Sources: CVE records from the CVE Program (cve.org). CVE® is a registered trademark of The MITRE Corporation. (https://www.cve.org/) This product uses data from the NVD API but is not endorsed or certified by the NVD. (https://nvd.nist.gov/) Known Exploited Vulnerabilities catalog from CISA. (https://www.cisa.gov/known-exploited-vulnerabilities-catalog) EPSS scores from FIRST (Exploit Prediction Scoring System). (https://www.first.org/epss/)_


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Canonical: https://rewindex.com/cve/CVE-2024-39891 · Markdown: https://rewindex.com/cve/CVE-2024-39891.md · JSON: https://rewindex.com/api/v1/cves/CVE-2024-39891 · Data licensed CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/) · Generated 2026-10-26T05:11:14.369Z