Amazon Linux AMI update for glibc

Published: 2021-07-13

Risk	High
Patch available	YES
Number of vulnerabilities	4
CVE-ID	CVE-2019-19126 CVE-2019-25013 CVE-2020-10029 CVE-2020-29573
CWE-ID	CWE-200 CWE-125 CWE-121 CWE-787
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	Amazon Linux AMI Operating systems & Components / Operating system
Vendor	Amazon Web Services

Security Bulletin

This security bulletin contains information about 4 vulnerabilities.

1) Information disclosure

EUVDB-ID: #VU30596

Risk: Low

CVSSv3.1: 2.9 [CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-19126

CWE-ID: CWE-200 - Information exposure

Exploit availability: No

Description

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

On the x86-64 architecture, the GNU C Library (aka glibc) before 2.31 fails to ignore the LD_PREFER_MAP_32BIT_EXEC environment variable during program execution after a security transition, allowing local attackers to restrict the possible mapping addresses for loaded libraries and thus bypass ASLR for a setuid program.

Mitigation

Update the affected packages:

i686:
    glibc-static-2.17-322.181.amzn1.i686
    glibc-utils-2.17-322.181.amzn1.i686
    glibc-headers-2.17-322.181.amzn1.i686
    glibc-2.17-322.181.amzn1.i686
    glibc-devel-2.17-322.181.amzn1.i686
    glibc-common-2.17-322.181.amzn1.i686
    glibc-debuginfo-2.17-322.181.amzn1.i686
    glibc-debuginfo-common-2.17-322.181.amzn1.i686
    nscd-2.17-322.181.amzn1.i686

src:
    glibc-2.17-322.181.amzn1.src

x86_64:
    nscd-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-common-2.17-322.181.amzn1.x86_64
    glibc-headers-2.17-322.181.amzn1.x86_64
    glibc-2.17-322.181.amzn1.x86_64
    glibc-static-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-2.17-322.181.amzn1.x86_64
    glibc-common-2.17-322.181.amzn1.x86_64
    glibc-devel-2.17-322.181.amzn1.x86_64
    glibc-utils-2.17-322.181.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1511.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) Out-of-bounds read

EUVDB-ID: #VU50329

Risk: Low

CVSSv3.1: 2.7 [CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C]

CVE-ID: CVE-2019-25013

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

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary condition in GNU C Library within the iconv feature when processing multi-byte input sequences in the EUC-KR encoding. A remote attacker can pass specially crafted input to the application, trigger out-of-bounds read error and perform a denial of service (DoS) attack.

Mitigation

Update the affected packages:

i686:
    glibc-static-2.17-322.181.amzn1.i686
    glibc-utils-2.17-322.181.amzn1.i686
    glibc-headers-2.17-322.181.amzn1.i686
    glibc-2.17-322.181.amzn1.i686
    glibc-devel-2.17-322.181.amzn1.i686
    glibc-common-2.17-322.181.amzn1.i686
    glibc-debuginfo-2.17-322.181.amzn1.i686
    glibc-debuginfo-common-2.17-322.181.amzn1.i686
    nscd-2.17-322.181.amzn1.i686

src:
    glibc-2.17-322.181.amzn1.src

x86_64:
    nscd-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-common-2.17-322.181.amzn1.x86_64
    glibc-headers-2.17-322.181.amzn1.x86_64
    glibc-2.17-322.181.amzn1.x86_64
    glibc-static-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-2.17-322.181.amzn1.x86_64
    glibc-common-2.17-322.181.amzn1.x86_64
    glibc-devel-2.17-322.181.amzn1.x86_64
    glibc-utils-2.17-322.181.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1511.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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

3) Stack-based buffer overflow

EUVDB-ID: #VU26388

Risk: High

CVSSv3.1: 7.1 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-10029

CWE-ID: CWE-121 - Stack-based buffer overflow

Exploit availability: No

Description

The vulnerability allows an attacker to execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within "sysdeps/ieee754/ldbl-96/e_rem_pio2l.c" in GNU C Library (aka glibc or libc6). An attacker can pas specially crafted input to the application and trigger a stack-based buffer overflow.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system or denial of service conditions.

Mitigation

Update the affected packages:

i686:
    glibc-static-2.17-322.181.amzn1.i686
    glibc-utils-2.17-322.181.amzn1.i686
    glibc-headers-2.17-322.181.amzn1.i686
    glibc-2.17-322.181.amzn1.i686
    glibc-devel-2.17-322.181.amzn1.i686
    glibc-common-2.17-322.181.amzn1.i686
    glibc-debuginfo-2.17-322.181.amzn1.i686
    glibc-debuginfo-common-2.17-322.181.amzn1.i686
    nscd-2.17-322.181.amzn1.i686

src:
    glibc-2.17-322.181.amzn1.src

x86_64:
    nscd-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-common-2.17-322.181.amzn1.x86_64
    glibc-headers-2.17-322.181.amzn1.x86_64
    glibc-2.17-322.181.amzn1.x86_64
    glibc-static-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-2.17-322.181.amzn1.x86_64
    glibc-common-2.17-322.181.amzn1.x86_64
    glibc-devel-2.17-322.181.amzn1.x86_64
    glibc-utils-2.17-322.181.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1511.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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

4) Out-of-bounds write

EUVDB-ID: #VU50362

Risk: Medium

CVSSv3.1: 5.2 [CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:O/RC:C]

CVE-ID: CVE-2020-29573

CWE-ID: CWE-787 - Out-of-bounds write

Exploit availability: No

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to a boundary within the sysdeps/i386/ldbl2mpn.c in the GNU C Library on x86 systems. A remote attacker can pass specially crafted data to the application that uses the vulnerable version of glibc and crash it.

Mitigation

Update the affected packages:

i686:
    glibc-static-2.17-322.181.amzn1.i686
    glibc-utils-2.17-322.181.amzn1.i686
    glibc-headers-2.17-322.181.amzn1.i686
    glibc-2.17-322.181.amzn1.i686
    glibc-devel-2.17-322.181.amzn1.i686
    glibc-common-2.17-322.181.amzn1.i686
    glibc-debuginfo-2.17-322.181.amzn1.i686
    glibc-debuginfo-common-2.17-322.181.amzn1.i686
    nscd-2.17-322.181.amzn1.i686

src:
    glibc-2.17-322.181.amzn1.src

x86_64:
    nscd-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-common-2.17-322.181.amzn1.x86_64
    glibc-headers-2.17-322.181.amzn1.x86_64
    glibc-2.17-322.181.amzn1.x86_64
    glibc-static-2.17-322.181.amzn1.x86_64
    glibc-debuginfo-2.17-322.181.amzn1.x86_64
    glibc-common-2.17-322.181.amzn1.x86_64
    glibc-devel-2.17-322.181.amzn1.x86_64
    glibc-utils-2.17-322.181.amzn1.x86_64

Vulnerable software versions

Amazon Linux AMI: All versions

External links

http://alas.aws.amazon.com/ALAS-2021-1511.html

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

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