SB2018120707 - Amazon Linux AMI update for ruby23
Published: December 7, 2018
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Security restrictions bypass (CVE-ID: CVE-2018-16396)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
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) Security restrictions bypass (CVE-ID: CVE-2018-16395)
CWE-ID: CWE-20 - Improper input validation
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear
The vulnerability allows a remote attacker to bypass security restrictions on the target system.
The weakness exists in OpenSSL::X509::Name due to the equality check is not correct if the value of an entity of the argument (right-hand side) starts with the value of the receiver (left-hand side). A remote attacker can supply malicious X.509 certificate to be passed and bypass security restrictions to conduct further attacks.
Remediation
Install update from vendor's website.