Amazon Linux AMI update for kernel

Published: 2020-03-13

Risk	Medium
Patch available	YES
Number of vulnerabilities	2
CVE-ID	CVE-2019-15918 CVE-2019-20096
CWE-ID	CWE-125 CWE-401
Exploitation vector	Network
Public exploit	N/A
Vulnerable software	Amazon Linux AMI Operating systems & Components / Operating system
Vendor	Amazon Web Services

Security Bulletin

This security bulletin contains information about 2 vulnerabilities.

1) Out-of-bounds read

EUVDB-ID: #VU30794

Risk: Low

CVSSv4.0: 5.9 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2019-15918

CWE-ID: CWE-125 - Out-of-bounds read

Exploit availability: No

Description

The vulnerability allows a local authenticated user to execute arbitrary code.

An issue was discovered in the Linux kernel before 5.0.10. SMB2_negotiate in fs/cifs/smb2pdu.c has an out-of-bounds read because data structures are incompletely updated after a change from smb30 to smb21.

Mitigation

Update the affected packages:

i686:
    kernel-devel-4.14.171-105.231.amzn1.i686
    perf-4.14.171-105.231.amzn1.i686
    perf-debuginfo-4.14.171-105.231.amzn1.i686
    kernel-tools-devel-4.14.171-105.231.amzn1.i686
    kernel-headers-4.14.171-105.231.amzn1.i686
    kernel-tools-debuginfo-4.14.171-105.231.amzn1.i686
    kernel-tools-4.14.171-105.231.amzn1.i686
    kernel-debuginfo-common-i686-4.14.171-105.231.amzn1.i686
    kernel-4.14.171-105.231.amzn1.i686
    kernel-debuginfo-4.14.171-105.231.amzn1.i686

src:
    kernel-4.14.171-105.231.amzn1.src

x86_64:
    kernel-tools-4.14.171-105.231.amzn1.x86_64
    kernel-4.14.171-105.231.amzn1.x86_64
    kernel-debuginfo-4.14.171-105.231.amzn1.x86_64
    kernel-tools-devel-4.14.171-105.231.amzn1.x86_64
    kernel-debuginfo-common-x86_64-4.14.171-105.231.amzn1.x86_64
    kernel-tools-debuginfo-4.14.171-105.231.amzn1.x86_64
    perf-debuginfo-4.14.171-105.231.amzn1.x86_64
    perf-4.14.171-105.231.amzn1.x86_64
    kernel-devel-4.14.171-105.231.amzn1.x86_64
    kernel-headers-4.14.171-105.231.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

CPE2.3

cpe:2.3:o:amazon_web_services:amazon_linux_ami:*:*:*:*:*:*:*:*

External links

https://alas.aws.amazon.com/ALAS-2020-1349.html

Q & A

Can this vulnerability be exploited remotely?

No. This vulnerability can be exploited locally. The attacker should have authentication credentials and successfully authenticate on the system.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.

2) Memory leak

EUVDB-ID: #VU30493

Risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2019-20096

CWE-ID: CWE-401 - Missing release of memory after effective lifetime