Known exploited · Twilio
CVE-2024-39891: Twilio Authy Information Disclosure Vulnerability
What it is
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.
- Vendor
- Twilio
- Product
- Authy
- Added to KEV
- July 23, 2024
- CISA due date
- August 13, 2024
- Ransomware use
- Unknown
- Weakness
- CWE-203: Observable Discrepancy
What CISA requires
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Forensic triage
No
What to do now
- Find every instance of Authy you run, including the forgotten ones, and check its version against the vendor advisory.
- Apply the vendor's fix or mitigation, before August 13, 2024 if you are bound by CISA's deadline, sooner if it faces the internet.
- Assume it was tried against you already: look for signs of exploitation from the date it was added, not from the day you patched.
References
H2 Security
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Start freeSource: CISA Known Exploited Vulnerabilities Catalog (public domain), catalog version 2026.10.01.