Amazon Linux AMI : openssl (ALAS-2019-1188)

Medium Nessus Plugin ID 123957

Synopsis

The remote Amazon Linux AMI host is missing a security update.

Description

A microprocessor side-channel vulnerability was found on SMT (e.g, Hyper-Threading) architectures. An attacker running a malicious process on the same core of the processor as the victim process can extract certain secret information. (CVE-2018-5407)

If an application encounters a fatal protocol error and then calls SSL_shutdown() twice (once to send a close_notify, and once to receive one) then OpenSSL can respond differently to the calling application if a 0 byte record is received with invalid padding compared to if a 0 byte record is received with an invalid MAC. If the application then behaves differently based on that in a way that is detectable to the remote peer, then this amounts to a padding oracle that could be used to decrypt data. In order for this to be exploitable 'non-stitched' ciphersuites must be in use. Stitched ciphersuites are optimised implementations of certain commonly used ciphersuites. Also the application must call SSL_shutdown() twice even if a protocol error has occurred (applications should not do this but some do anyway).

(CVE-2019-1559)

Solution

Run 'yum update openssl' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2019-1188.html

Plugin Details

Severity: Medium

ID: 123957

File Name: ala_ALAS-2019-1188.nasl

Version: 1.2

Type: local

Agent: unix

Published: 2019/04/10

Updated: 2019/04/11

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 4.3

Temporal Score: 3.4

Vector: CVSS2#AV:N/AC:M/Au:N/C:P/I:N/A:N

Temporal Vector: CVSS2#E:POC/RL:OF/RC:C

CVSS v3.0

Base Score: 5.9

Temporal Score: 5.3

Vector: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Temporal Vector: CVSS:3.0/E:P/RL:O/RC:C

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:openssl, p-cpe:/a:amazon:linux:openssl-debuginfo, p-cpe:/a:amazon:linux:openssl-devel, p-cpe:/a:amazon:linux:openssl-perl, p-cpe:/a:amazon:linux:openssl-static, cpe:/o:amazon:linux

Required KB Items: Host/local_checks_enabled, Host/AmazonLinux/release, Host/AmazonLinux/rpm-list

Exploit Available: true

Exploit Ease: Exploits are available

Patch Publication Date: 2019/04/09

Vulnerability Publication Date: 2018/11/15

Reference Information

CVE: CVE-2018-5407, CVE-2019-1559

ALAS: 2019-1188