Amazon Linux AMI update for xorg-x11-server

1) Out-of-bounds read

EUVDB-ID: #VU46028

Risk: Low

CVSSv3.1: 2.5 [CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-14345

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

Exploit availability: No

Description

The vulnerability allows a local user to gain access to potentially sensitive information.

The vulnerability exists due to a boundary condition in XkbSetNames(). A local user can run a specially crafted program to trigger out-of-bounds read error and read contents of memory on the system.

Mitigation

Update the affected packages:

i686:
    xorg-x11-server-Xvfb-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.i686
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.i686
    xorg-x11-server-common-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.i686
    xorg-x11-server-devel-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.i686

noarch:
    xorg-x11-server-source-1.17.4-18.43.amzn1.noarch

src:
    xorg-x11-server-1.17.4-18.43.amzn1.src

x86_64:
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-devel-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-common-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xvfb-1.17.4-18.43.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

http://alas.aws.amazon.com/ALAS-2020-1469.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) Integer underflow

EUVDB-ID: #VU46029

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-14346

CWE-ID: CWE-191 - Integer underflow

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to integer underflow in the XIChangeHierarchy(). A local user can send a specially crafted request to the affected application, trigger integer underflow and execute arbitrary code on the target system with elevated privileges.

Mitigation

Update the affected packages:

i686:
    xorg-x11-server-Xvfb-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.i686
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.i686
    xorg-x11-server-common-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.i686
    xorg-x11-server-devel-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.i686

noarch:
    xorg-x11-server-source-1.17.4-18.43.amzn1.noarch

src:
    xorg-x11-server-1.17.4-18.43.amzn1.src

x86_64:
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-devel-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-common-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xvfb-1.17.4-18.43.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

http://alas.aws.amazon.com/ALAS-2020-1469.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.

3) Integer underflow

EUVDB-ID: #VU46030

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-14361

CWE-ID: CWE-191 - Integer underflow

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to integer underflow in the XkbSelectEvents(). A local user can send a specially crafted request to the affected application, trigger integer underflow and execute arbitrary code on the target system with elevated privileges.

Mitigation

Update the affected packages:

i686:
    xorg-x11-server-Xvfb-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.i686
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.i686
    xorg-x11-server-common-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.i686
    xorg-x11-server-devel-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.i686

noarch:
    xorg-x11-server-source-1.17.4-18.43.amzn1.noarch

src:
    xorg-x11-server-1.17.4-18.43.amzn1.src

x86_64:
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-devel-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-common-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xvfb-1.17.4-18.43.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

http://alas.aws.amazon.com/ALAS-2020-1469.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.

4) Integer underflow

EUVDB-ID: #VU46031

Risk: Low

CVSSv3.1: 7.7 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-14362

CWE-ID: CWE-191 - Integer underflow

Exploit availability: No

Description

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists due to integer underflow in the XRecordRegisterClients(). A local user can send a specially crafted request to the affected application, trigger integer underflow and execute arbitrary code on the target system with elevated privileges.

Mitigation

Update the affected packages:

i686:
    xorg-x11-server-Xvfb-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.i686
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.i686
    xorg-x11-server-common-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.i686
    xorg-x11-server-devel-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.i686
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.i686

noarch:
    xorg-x11-server-source-1.17.4-18.43.amzn1.noarch

src:
    xorg-x11-server-1.17.4-18.43.amzn1.src

x86_64:
    xorg-x11-server-Xorg-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xnest-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-debuginfo-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xephyr-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xdmx-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-devel-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-common-1.17.4-18.43.amzn1.x86_64
    xorg-x11-server-Xvfb-1.17.4-18.43.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

http://alas.aws.amazon.com/ALAS-2020-1469.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.

Risk	Low
Patch available	YES
Number of vulnerabilities	4
CVE-ID	CVE-2020-14345 CVE-2020-14346 CVE-2020-14361 CVE-2020-14362
CWE-ID	CWE-125 CWE-191
Exploitation vector	Local
Public exploit	N/A
Vulnerable software	Amazon Linux AMI Operating systems & Components / Operating system
Vendor	Amazon Web Services