CVE-2024-39891

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.)

CVSS v3.1 Score

5.3

MEDIUM

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CISA Known Exploited Vulnerability

This vulnerability is actively exploited in the wild.

Added: Jul 23, 2024 Remediation due: Aug 13, 2024

Weakness Type (CWE)

CWE-203 CWE-203

Affected Products

Vendor	Product	Versions
twilio	authy	< 26.1.0
twilio	authy_authenticator	< 25.1.0

References

Other References

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.twilio.com/docs/usage/security/reporting-vulnerabilities https://www.twilio.com/en-us/changelog 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.twilio.com/docs/usage/security/reporting-vulnerabilities https://www.twilio.com/en-us/changelog https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2024-39891

Frequently Asked Questions

What is 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.) It has a CVSS v3.1 base score of 5.3 (MEDIUM). This vulnerability is listed in CISA's Known Exploited Vulnerabilities catalog, indicating active exploitation in the wild.

How severe is CVE-2024-39891? +

CVE-2024-39891 has a CVSS v3.1 score of 5.3 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-39891? +

CVE-2024-39891 affects products from twilio, specifically: authy, authy_authenticator. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-39891? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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