CVE-2024-37893: Auth Bypass (CVSS 5.9)

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.

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CVSS v3.1 Score

5.9

MEDIUM

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

Weakness Type (CWE)

CWE-287 Improper Authentication

CWE-288 CWE-288

References

Other References

https://github.com/firefly-iii/firefly-iii/security/advisories/GHSA-4gm4-c4mh-4p7w https://owasp.org/www-community/attacks/Password_Spraying_Attack https://www.menlosecurity.com/what-is/highly-evasive-adaptive-threats-heat/mfa-bypass https://github.com/firefly-iii/firefly-iii/security/advisories/GHSA-4gm4-c4mh-4p7w https://owasp.org/www-community/attacks/Password_Spraying_Attack https://www.menlosecurity.com/what-is/highly-evasive-adaptive-threats-heat/mfa-bypass

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. It has a CVSS v3.1 base score of 5.9 (MEDIUM).

How severe is CVE-2024-37893? +

CVE-2024-37893 has a CVSS v3.1 score of 5.9 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

How do I check if I'm vulnerable to CVE-2024-37893? +

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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CVE-2024-37893