SB2021071501 - Gentoo update for urllib3

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Improper validation of certificate with host mismatch (CVE-ID: CVE-2021-28363)

The vulnerability allows a remote attacker to perform MitM attack.

The vulnerability exists due to urllib3 library for Python omits SSL certificate validation in some cases involving HTTPS to HTTPS proxies. The initial connection to the HTTPS proxy (if an SSLContext isn't given via proxy_config) doesn't verify the hostname of the certificate. This means certificates for different servers that still validate properly with the default urllib3 SSLContext will be silently accepted. A remote attacker can supply a valid SSL certificate for a different hostname and perform Man-in-the-Middle (MitM) attack.

2) Resource exhaustion (CVE-ID: CVE-2021-33503)

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

The vulnerability exists due to improper input validation in urllib3 when processing URL with multiple "@" characters in the authority component. A remote attacker can trigger resource exhaustion and perform a denial of service (DoS) attack.

Remediation

Install update from vendor's website.

References

• https://security.gentoo.org/
• https://security.gentoo.org/glsa/202107-36