Amazon Linux 2 : openssl (ALAS-2019-1362)

Medium Nessus Plugin ID 131030

Synopsis

The remote Amazon Linux 2 host is missing a security update.

Description

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).
Fixed in OpenSSL 1.0.2r (Affected 1.0.2-1.0.2q). (CVE-2019-1559)

The OpenSSL DSA signature algorithm has been shown to be vulnerable to a timing side channel attack. An attacker could use variations in the signing algorithm to recover the private key. Fixed in OpenSSL 1.1.1a (Affected 1.1.1). Fixed in OpenSSL 1.1.0j (Affected 1.1.0-1.1.0i).
Fixed in OpenSSL 1.0.2q (Affected 1.0.2-1.0.2p). (CVE-2018-0734)

Solution

Run 'yum update openssl' to update your system.

See Also

https://alas.aws.amazon.com/AL2/ALAS-2019-1362.html

Plugin Details

Severity: Medium

ID: 131030

File Name: al2_ALAS-2019-1362.nasl

Version: 1.2

Type: local

Agent: unix

Published: 2019/11/15

Updated: 2019/12/12

Dependencies: 12634

Risk Information

Risk Factor: Medium

CVSS v2.0

Base Score: 4.3

Temporal Score: 3.2

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

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

CVSS v3.0

Base Score: 5.9

Temporal Score: 5.2

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:U/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-libs, p-cpe:/a:amazon:linux:openssl-perl, p-cpe:/a:amazon:linux:openssl-static, cpe:/o:amazon:linux:2

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

Exploit Ease: No known exploits are available

Patch Publication Date: 2019/11/14

Vulnerability Publication Date: 2018/10/30

Reference Information

CVE: CVE-2018-0734, CVE-2019-1559

ALAS: 2019-1362