USN-4692-1: tar vulnerabilities

Releases

• Ubuntu 20.10
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM
• Ubuntu 14.04 ESM
• Ubuntu 12.04

Packages

• tar - GNU version of the tar archiving utility

Details

Chris Siebenmann discovered that tar incorrectly handled extracting files
resized during extraction when invoked with the --sparse flag. An attacker
could possibly use this issue to cause a denial of service. This issue
only affected Ubuntu 12.04 ESM, Ubuntu 14.04 ESM, Ubuntu 16.04 LTS and
Ubuntu 18.04 LTS. (CVE-2018-20482)

Daniel Axtens discovered that tar incorrectly handled certain malformed
tar files. If a user or automated system were tricked into processing a
specially crafted tar archive, a remote attacker could use this issue to
cause tar to crash, resulting in a denial of service. (CVE-2019-9923)

Update instructions

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

Ubuntu 20.10

• tar - 1.30+dfsg-7ubuntu0.20.10.1

Ubuntu 20.04

• tar - 1.30+dfsg-7ubuntu0.20.04.1

Ubuntu 18.04

• tar - 1.29b-2ubuntu0.2

Ubuntu 16.04

• tar - 1.28-2.1ubuntu0.2

Ubuntu 14.04

• tar - 1.27.1-1ubuntu0.1+esm1
  Available with Ubuntu Pro

Ubuntu 12.04

• tar - 1.26-4ubuntu1.2

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

References

• CVE-2018-20482
• CVE-2019-9923