#VU55292 Improper Restriction of Excessive Authentication Attempts in Firefly III - CVE-2021-3663

Vulnerability identifier: #VU55292

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3663

CWE-ID: CWE-307

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Firefly III
Client/Desktop applications / Other client software

Vendor: James Cole

Description

The vulnerability allows a remote attacker to compromise the target system.

The vulnerability exists due to the affected software does not implement sufficient measures to prevent multiple failed authentication attempts within in a short time frame. A remote attacker can perform a brute-force attack and gain access to sensitive information on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Firefly III: 5.5.0 - 5.5.12

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External links
https://huntr.dev/bounties/497bdf6d-7dba-49c3-8011-1c64dfbb3380
https://github.com/firefly-iii/firefly-iii/commit/afc9f4b7ebc8a240c85864a6e1abda62bfeefae8

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.