Denial of service in Pallets Flask

1) Input validation error

EUVDB-ID: #VU18150

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-2018-1000656

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists due to insufficient validation of user-supplied input when processing JSON data in incorrect encoding. A remote attacker can supply a specially crafted JSON string and consume all available memory resources.

Successful exploitation of the vulnerability may allow an attacker to perform denial of service (DoS) attack.

Mitigation

Update to version 0.12.3.

Vulnerable software versions

Flask: 0.1 - 0.12.2

External links

http://github.com/pallets/flask/pull/2691
http://github.com/pallets/flask/releases/tag/0.12.3
http://security.netapp.com/advisory/ntap-20190221-0001/

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.