Amazon Linux AMI : krb5 (ALAS-2016-691)

high Nessus Plugin ID 90633

Synopsis

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

Description

An out-of-bounds read flaw was found in the kadmind service of MIT Kerberos. An authenticated attacker could send a maliciously crafted message to force kadmind to read beyond the end of allocated memory, and write the memory contents to the KDC database if the attacker has write permission, leading to information disclosure. (CVE-2015-8629)

A NULL pointer dereference flaw was found in the procedure used by the MIT Kerberos kadmind service to store policies: the kadm5_create_principal_3() and kadm5_modify_principal() function did not ensure that a policy was given when KADM5_POLICY was set. An authenticated attacker with permissions to modify the database could use this flaw to add or modify a principal with a policy set to NULL, causing the kadmind service to crash. (CVE-2015-8630)

A memory leak flaw was found in the krb5_unparse_name() function of the MIT Kerberos kadmind service. An authenticated attacker could repeatedly send specially crafted requests to the server, which could cause the server to consume large amounts of memory resources, ultimately leading to a denial of service due to memory exhaustion.
(CVE-2015-8631)

Solution

Run 'yum update krb5' to update your system.

See Also

https://alas.aws.amazon.com/ALAS-2016-691.html

Plugin Details

Severity: High

ID: 90633

File Name: ala_ALAS-2016-691.nasl

Version: 2.3

Type: local

Agent: unix

Published: 4/22/2016

Updated: 4/18/2018

Supported Sensors: Frictionless Assessment AWS, Frictionless Assessment Agent, Nessus Agent, Agentless Assessment, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 3.6

CVSS v2

Risk Factor: Medium

Base Score: 6.8

Vector: CVSS2#AV:N/AC:L/Au:S/C:N/I:N/A:C

CVSS v3

Risk Factor: High

Base Score: 7.5

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

Vulnerability Information

CPE: p-cpe:/a:amazon:linux:krb5-debuginfo, p-cpe:/a:amazon:linux:krb5-devel, p-cpe:/a:amazon:linux:krb5-libs, p-cpe:/a:amazon:linux:krb5-pkinit-openssl, p-cpe:/a:amazon:linux:krb5-server, p-cpe:/a:amazon:linux:krb5-server-ldap, p-cpe:/a:amazon:linux:krb5-workstation, cpe:/o:amazon:linux

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

Patch Publication Date: 4/21/2016

Reference Information

CVE: CVE-2015-8629, CVE-2015-8630, CVE-2015-8631

ALAS: 2016-691