A json-c security update has been released for Ubuntu Linux 20.04 LTS, 19.10, 18.04 LTS, 16.04 LTS, 14.04 ESM, and 12.04 ESM.

USN-4360-4: json-c vulnerability

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Ubuntu Security Notice USN-4360-4
May 28, 2020

json-c vulnerability
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A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 20.04 LTS
- Ubuntu 19.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 ESM
- Ubuntu 12.04 ESM

Summary:

json-c could be made to execute arbitrary code if it received
a specially crafted JSON file.

Software Description:
- json-c: JSON manipulation library

Details:

USN-4360-1 fixed a vulnerability in json-c. The security fix introduced a
memory leak that was reverted in USN-4360-2 and USN-4360-3. This update provides
the correct fix update for CVE-2020-12762.

Original advisory details:

It was discovered that json-c incorrectly handled certain JSON files.
An attacker could possibly use this issue to execute arbitrary code.

Update instructions:

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

Ubuntu 20.04 LTS:
libjson-c4 0.13.1+dfsg-7ubuntu0.3

Ubuntu 19.10:
libjson-c4 0.13.1+dfsg-4ubuntu0.3

Ubuntu 18.04 LTS:
libjson-c3 0.12.1-1.3ubuntu0.3

Ubuntu 16.04 LTS:
libjson-c2 0.11-4ubuntu2.6
libjson0 0.11-4ubuntu2.6

Ubuntu 14.04 ESM:
libjson-c2 0.11-3ubuntu1.2+esm3
libjson0 0.11-3ubuntu1.2+esm3

Ubuntu 12.04 ESM:
libjson0 0.9-1ubuntu1.4

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

References:
  https://usn.ubuntu.com/4360-4
  https://usn.ubuntu.com/4360-1
CVE-2020-12762

Package Information:
  https://launchpad.net/ubuntu/+source/json-c/0.13.1+dfsg-7ubuntu0.3
  https://launchpad.net/ubuntu/+source/json-c/0.13.1+dfsg-4ubuntu0.3
  https://launchpad.net/ubuntu/+source/json-c/0.12.1-1.3ubuntu0.3
  https://launchpad.net/ubuntu/+source/json-c/0.11-4ubuntu2.6