SB2020081273 - Amazon Linux AMI update for ruby20

Description

This security bulletin contains information about 2 secuirty vulnerabilities.

1) Security restrictions bypass (CVE-ID: CVE-2018-16396)

The vulnerability allows a remote attacker to bypass security restrictions on the target system.

The weakness exists due to the tainted flags are not propagated with the B, b, H, and h directives. A remote attacker can supply inputs by Array#pack and/or String#unpack with these directives and checks the reliability with tainted flags and cause the check to be wrong to bypass security restrictions and conduct further attacks.

2) Input validation error (CVE-ID: CVE-2020-10663)

The vulnerability allows a remote non-authenticated attacker to manipulate data.

The JSON gem through 2.2.0 for Ruby, as used in Ruby 2.4 through 2.4.9, 2.5 through 2.5.7, and 2.6 through 2.6.5, has an Unsafe Object Creation Vulnerability. This is quite similar to CVE-2013-0269, but does not rely on poor garbage-collection behavior within Ruby. Specifically, use of JSON parsing methods can lead to creation of a malicious object within the interpreter, with adverse effects that are application-dependent.

Remediation

Install update from vendor's website.

References

• https://alas.aws.amazon.com/ALAS-2020-1416.html