SB2021112503 - Multiple vulnerabilities in Ruby cgi gem

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Buffer overflow (CVE-ID: CVE-2021-41816)

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

The vulnerability exists due to a boundary error in CGI.escape_html. A remote attacker can trigger memory corruption and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

2) Spoofing attack (CVE-ID: CVE-2021-41819)

The vulnerability allows a remote attacker to perform spoofing attack.

The vulnerability exists due to incorrect processing of user-supplied data in CGI::Cookie.parse. A remote attacker can spoof page content.

Remediation

Install update from vendor's website.

References

• https://www.ruby-lang.org/en/news/2021/11/24/buffer-overrun-in-cgi-escape_html-cve-2021-41816/
• https://www.ruby-lang.org/en/news/2021/11/24/cookie-prefix-spoofing-in-cgi-cookie-parse-cve-2021-41819/