Gentoo update for glibc

Published: 2021-01-25

Risk	High
Patch available	YES
Number of vulnerabilities	5
CVE-ID	CVE-2016-10228 CVE-2020-1752 CVE-2020-29562 CVE-2020-29573 CVE-2020-6096
CWE-ID	CWE-20 CWE-416 CWE-617 CWE-787 CWE-190
Exploitation vector	Network
Public exploit	Public exploit code for vulnerability #5 is available.
Vulnerable software	Gentoo Linux Operating systems & Components / Operating system sys-libs/glibc Operating systems & Components / Operating system package or component
Vendor	Gentoo

Security Bulletin

This security bulletin contains information about 5 vulnerabilities.

1) Input validation error

EUVDB-ID: #VU54337

Risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2016-10228

CWE-ID: CWE-20 - Improper input validation

Exploit availability: No

Description

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

The vulnerability exists due to insufficient validation of user-supplied input. The iconv program in the GNU C Library (aka glibc or libc6) 2.31 and earlier, when invoked with multiple suffixes in the destination encoding (TRANSLATE or IGNORE) along with the -c option, enters an infinite loop when processing invalid multi-byte input sequences, leading to a denial of service.

Mitigation

Update the affected packages.
sys-libs/glibc to version: 2.32-r5

Vulnerable software versions

Gentoo Linux: All versions

sys-libs/glibc: before 2.32-r5

CPE2.3

External links

https://security.gentoo.org/glsa/202101-20

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.

2) Use-after-free

EUVDB-ID: #VU26628

Risk: High

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:Amber]

CVE-ID: CVE-2020-1752

CWE-ID: CWE-416 - Use After Free

Exploit availability: No

Description

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

The vulnerability exists due to a use-after-free error within the glob() function in glibc in the way the tilde expansion was carried out. Directory paths containing an initial tilde followed by a valid username are affected by this issue. A local user can create a specially crafted path that, when processed by the glob() function, would potentially lead to arbitrary code execution.

Mitigation

Update the affected packages.
sys-libs/glibc to version: 2.32-r5

Vulnerable software versions

Gentoo Linux: All versions

sys-libs/glibc: before 2.32-r5

CPE2.3

External links

https://security.gentoo.org/glsa/202101-20

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) Reachable Assertion

EUVDB-ID: #VU49670

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-2020-29562

CWE-ID: CWE-617 - Reachable Assertion

Exploit availability: No

Description

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

The vulnerability exists due to a reachable assertion when converting UCS4 text containing an irreversible character in the iconv function in the GNU C Library (aka glibc or libc6). A remote attacker can pass specially crafted data to the library, trigger an assertion failure and preform a denial of service attack.

Mitigation

Update the affected packages.
sys-libs/glibc to version: 2.32-r5

Vulnerable software versions

Gentoo Linux: All versions

sys-libs/glibc: before 2.32-r5

CPE2.3

External links

https://security.gentoo.org/glsa/202101-20

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

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

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.
sys-libs/glibc to version: 2.32-r5

Vulnerable software versions

Gentoo Linux: All versions

sys-libs/glibc: before 2.32-r5

CPE2.3

External links

https://security.gentoo.org/glsa/202101-20

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.

5) Integer overflow

EUVDB-ID: #VU28193

Risk: Medium

CVSSv4.0: 6.8 [CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P/U:Green]

CVE-ID: CVE-2020-6096

CWE-ID: CWE-190 - Integer overflow

Exploit availability: Yes

Description

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

The vulnerability exists due to integer overflow within the the ARMv7 memcpy() implementation of GNU glibc 2.30.9000. A remote attacker can pass specially crafted data to the application, trigger integer overflow and execute arbitrary code on the target system.

Successful exploitation of this vulnerability may result in complete compromise of vulnerable system.

Mitigation

Update the affected packages.
sys-libs/glibc to version: 2.32-r5

Vulnerable software versions

Gentoo Linux: All versions

sys-libs/glibc: before 2.32-r5

CPE2.3

External links

https://security.gentoo.org/glsa/202101-20

Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability. However, proof of concept for this vulnerability is available.