#VU80753 Inefficient regular expression complexity in Redcloth - CVE-2023-31606

Vulnerability identifier: #VU80753

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-2023-31606

CWE-ID: CWE-1333

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Redcloth

Vendor: Promptworks

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 untrusted input with a regular expressions within the sanitize_html() function in lib/redcloth/formatters/html.rb. A remote attacker can pass specially crafted data to the application and perform regular expression denial of service (ReDos) attack.

Mitigation
Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

Redcloth: 0.4 - 4.3.2

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External links
https://github.com/e23e/CVE-2023-31606#readme
https://github.com/jgarber/redcloth/issues/73
https://github.com/jgarber/redcloth/pull/75/files

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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.