1. Ubuntu Security Notices
  2. USN-4954-1

USN-4954-1: GNU C Library vulnerabilities

Publication date

14 May 2021

Overview

Several security issues were fixed in GNU C Library.

Releases

Packages

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)

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

After a standard system update you need to reboot your computer to make all the necessary changes.

Learn more about how to get the fixes.

The problem can be corrected by updating your system to the following package versions:

Ubuntu Release Package Version
16.04 xenial libc6 –  2.23-0ubuntu11.3

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References

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