PatchTheCVECVE-2024-39891: Twilio Authy Information Disclosure Vulnerability
CVE-2024-39891 is a medium-severity flaw (CVSS 5.3) affecting authy, authy authenticator, reported as exploited in the wild. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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.)
Why this priority
- Exploited in the wild (CISA KEV)
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 5.3 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 1.7% (top 23%) |
| CISA exploited list | Yes, fix due 2024-08-13 |
| Weakness | CWE-203 |
| Published | 2024-07-02 |
| Last modified | 2026-06-17 |
Last updated 2026-06-17 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Exploited Added to the CISA Known Exploited Vulnerabilities list
- Deadline CISA due date for US federal agencies to patch
- Updated Record last modified
Exact fixes by distribution
Public exploits and detection
Public code exists for this CVE. Treat unpatched systems as at risk, and only run PoCs in a lab.
- Write-up: www.bleepingcomputer.com/news/security/hackers-abused-api-to-verify-millions-of-authy-mfa-
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2024-39891?
authy: upgrade to 26.1.0; authy authenticator: upgrade to 25.1.0. Exact commands for each OS are on this page.
Is CVE-2024-39891 being exploited?
Yes. CVE-2024-39891 is on the CISA Known Exploited Vulnerabilities list, so treat it as patch-now.
What does CVE-2024-39891 affect?
CVE-2024-39891 affects authy, authy authenticator. Severity is medium (CVSS 5.3). 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 accept
How urgent is CVE-2024-39891?
Priority 68/100. Exploited in the wild (CISA KEV); Remotely exploitable, no login, no user action
Software pages
Android vulnerabilities · iOS vulnerabilities · Twilio vulnerabilities