[USN-4954-1] GNU C Library vulnerabilities

========================================================================== Ubuntu Security Notice USN-4954-1 May 14, 2021
glibc vulnerabilities ==========================================================================
A security issue affects these releases of Ubuntu and its derivatives:
– Ubuntu 16.04 LTS
Summary:
Several security issues were fixed in GNU C Library.
Software Description: – glibc: GNU C Library
Details:
Jason Royes and Samuel Dytrych discovered that the memcpy() implementation for 32 bit ARM processors in the GNU C Library contained an integer underflow vulnerability. An attacker could possibly use this to cause a denial of service (application crash) or execute arbitrary code. (CVE-2020-6096)
It was discovered that the POSIX regex implementation in the GNU C Library did not properly parse alternatives. An attacker could use this to cause a denial of service. (CVE-2009-5155)
Update instructions:
The problem can be corrected by updating your system to the following package versions:
Ubuntu 16.04 LTS: libc6 2.23-0ubuntu11.3
After a standard system update you need to reboot your computer to make all the necessary changes.
References: ubuntu.com/security/notices/USN-4954-1 CVE-2009-5155, CVE-2020-6096