SB2021021104 - Multiple vulnerabilities in Ruby on Rails

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Incorrect Regular Expression (CVE-ID: CVE-2021-22880)

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

The vulnerability exists due to incorrect regular expression for money processing format in the PostgreSQL adapter. A remote attacker can pass specially crafted input to the application and perform a regular expression denial of service (ReDOS) attack.

2) Open redirect (CVE-ID: CVE-2021-22881)

The vulnerability allows a remote attacker to redirect victims to arbitrary URL.

The vulnerability exists due to improper sanitization of user-supplied data, when the allowed host starts with a dot. A remote attacker can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.

Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.

Remediation

Install update from vendor's website.

References

• https://github.com/rails/rails/releases/tag/v6.1.2.1
• https://github.com/rails/rails/releases/tag/v6.0.3.5
• https://github.com/rails/rails/releases/tag/v5.2.4.5