#VU64034 Code Injection in JSON schema - CVE-2021-3918

Vulnerability identifier: #VU64034

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2021-3918

CWE-ID: CWE-94

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
JSON schema
Web applications / JS libraries

Vendor: Tom de Grunt

Description

The disclosed vulnerability allows a remote attacker to execute arbitrary code on the system.

The vulnerability exists due to insufficient sanitization of user-supplied data during the validation of a JSON object. A remote attacker can pass a specially crafted JSON file for validation and execute arbitrary code.

Mitigation
Install update from vendor's website.

Vulnerable software versions

JSON schema: 0.0.0 - 0.3.2

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External links
https://github.com/kriszyp/json-schema/commit/22f146111f541d9737e832823699ad3528ca7741
https://huntr.dev/bounties/bb6ccd63-f505-4e3a-b55f-cd2662c261a9

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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.