Denial of service in musl libc

Published: 2020-11-20

Risk	Medium
Patch available	NO
Number of vulnerabilities	1
CVE ID	CVE-2020-28928
CWE ID	CWE-835
Exploitation vector	Network
Public exploit	N/A
Vulnerable software Subscribe	musl libc Universal components / Libraries / Libraries used by multiple products
Vendor	GNU

Security Advisory

This security advisory describes one medium risk vulnerability.

1) Infinite loop

Risk: Medium

CVSSv3.1: 6.9 [CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:U/RL:U/RC:C] [PCI]

CVE-ID: CVE-2020-28928

CWE-ID: CWE-835 - Loop with Unreachable Exit Condition ('Infinite Loop')

Exploit availability: No

Description

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

The vulnerability exists due to infinite loop within the wcsnrtombs() function in musl libc. A remote attacker can consume all available system resources and cause denial of service conditions.

Mitigation

Cybersecurity Help is currently unaware of any official solution to address this vulnerability.

Vulnerable software versions

musl libc: 0.5.0, 0.5.9, 0.6.0, 0.7.0, 0.7.1, 0.7.5, 0.7.6, 0.7.7, 0.7.8, 0.7.9, 0.7.10, 0.7.11, 0.7.12, 0.8.0, 0.8.1, 0.8.2, 0.8.3, 0.8.4, 0.8.5, 0.8.6, 0.8.7, 0.8.8, 0.8.9, 0.8.10, 0.9.0, 0.9.1, 0.9.3, 0.9.4, 0.9.5, 0.9.6, 0.9.7, 0.9.8, 0.9.9, 0.9.10, 0.9.11, 0.9.12, 0.9.13, 0.9.14, 0.9.15, 1.0.0, 1.0.1, 1.0.2, 1.0.3, 1.0.4, 1.0.5, 1.1.0, 1.1.1, 1.1.2, 1.1.3, 1.1.4, 1.1.5, 1.1.6, 1.1.7, 1.1.8, 1.1.9, 1.1.10, 1.1.11, 1.1.12, 1.1.13, 1.1.14, 1.1.15, 1.1.16, 1.1.17, 1.1.18, 1.1.19, 1.1.20, 1.1.21, 1.1.22, 1.1.23, 1.1.24, 1.2.0, 1.2.1

CPE

External links

http://seclists.org/oss-sec/2020/q4/152

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.