Remote denial of service in FastAPI

1) Inefficient regular expression complexity

EUVDB-ID: #VU86533

Risk: Medium

CVSSv3.1: 6.5 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2024-24762

CWE-ID: CWE-1333 - Inefficient Regular Expression Complexity

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to insufficient input validation when processing value of the "Content-Type" HTTP header with a regular expressions. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.

Mitigation

Install update from vendor's website.

Vulnerable software versions

FastAPI: 0.1.11 - 0.109.0

External links

http://github.com/tiangolo/fastapi/security/advisories/GHSA-qf9m-vfgh-m389
http://github.com/tiangolo/fastapi/commit/9d34ad0ee8a0dfbbcce06f76c2d5d851085024fc
http://github.com/tiangolo/fastapi/releases/tag/0.109.1

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.