#VU83018 Input validation error in Discourse - CVE-2023-47120

Vulnerability identifier: #VU83018

Vulnerability risk: Medium

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

CVE-ID: CVE-2023-47120

CWE-ID: CWE-20

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Discourse
Web applications / Forum & blogging software

Vendor: Civilized Discourse Construction Kit, Inc.

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 within the Onebox favicon URL. A remote attacker can pass specially crafted input to the application and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Discourse: 3.1.0 beta6 - 3.2.0 beta2

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External links
https://github.com/discourse/discourse/security/advisories/GHSA-77cw-xhj8-hfp3
https://github.com/discourse/discourse/commit/95a82d608d6377faf68a0e2c5d9640b043557852
https://github.com/discourse/discourse/commit/e910dd09140cb4abc3a563b95af4a137ca7fa0ce

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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.