CVE-2024-37893: Firefly III is a free and open source personal finance manager. In affected versions an MFA bypass in the Firefly III OAuth flow may allow malicious u...

Description

Firefly III is a free and open source personal finance manager. In affected versions an MFA bypass in the Firefly III OAuth flow may allow malicious users to bypass the MFA-check. This allows malicious users to use password spraying to gain access to Firefly III data using passwords stolen from other sources. As OAuth applications are easily enumerable using an incrementing id, an attacker could try sign an OAuth application up to a users profile quite easily if they have created one. The attacker would also need to know the victims username and password. This problem has been patched in Firefly III v6.1.17 and up. Users are advised to upgrade. Users unable to upgrade should Use a unique password for their Firefly III instance and store their password securely, i.e. in a password manager.

Metrics

CVSS 3.1

5.9/10

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

EPSS Probability

0.59%

43.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

References

Timeline

Published: Jun 17, 2024
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2024-37893?

Firefly III is a free and open source personal finance manager. In affected versions an MFA bypass in the Firefly III OAuth flow may allow malicious users to bypass the MFA-check. This allows malicious users to use password spraying to gain access to Firefly III data using passwords stolen from other sources. As OAuth applications are easily enumerable using an incrementing id, an attacker could try sign an OAuth application up to a users profile quite easily if they have created one. The attacker would also need to know the victims username and password. This problem has been patched in Firefly III v6.1.17 and up. Users are advised to upgrade. Users unable to upgrade should Use a unique password for their Firefly III instance and store their password securely, i.e. in a password manager.

How severe is CVE-2024-37893?

CVE-2024-37893 has a CVSS score of 5.9/10 (MEDIUM severity). The EPSS model estimates a 0.59% probability of exploitation in the next 30 days.

How do I fix CVE-2024-37893?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.