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Ubuntu Security Notice USN-4179-1
November 07, 2019

fribidi vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 19.10
- Ubuntu 19.04

Summary:

Applications using FriBidi could be made to crash or run programs as your
login if it displayed specially crafted text.

Software Description:
- fribidi: Free Implementation of the Unicode BiDi algorithm (utility)

Details:

Alex Murray discovered a stack-based buffer overflow when handling a large
number of unicode isolate directives. An attacker could use this to cause a
denial of service or possibly execute arbitrary code.

Update instructions:

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

Ubuntu 19.10:
  libfribidi0                     1.0.5-3.1ubuntu0.19.10.1

Ubuntu 19.04:
  libfribidi0                     1.0.5-3.1ubuntu0.19.04.1

In general, a standard system update will make all the necessary changes.

References:
  https://usn.ubuntu.com/4179-1
  CVE-2019-18397

Package Information:
  https://launchpad.net/ubuntu/+source/fribidi/1.0.5-3.1ubuntu0.19.10.1
  https://launchpad.net/ubuntu/+source/fribidi/1.0.5-3.1ubuntu0.19.04.1