==========================================================================
Ubuntu Security Notice USN-4763-1
March 11, 2021

pillow vulnerabilities
==========================================================================

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

- Ubuntu 20.10
- Ubuntu 20.04 LTS
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Pillow.

Software Description:
- pillow: Python Imaging Library

Details:

It was discovered that Pillow incorrectly handled certain Tiff image files.
If a user or automated system were tricked into opening a specially-crafted
Tiff file, a remote attacker could cause Pillow to crash, resulting in a
denial of service, or possibly execute arbitrary code. This issue only
affected Ubuntu 20.04 LTS and Ubuntu 20.10. (CVE-2021-25289,
CVE-2021-25291)

It was discovered that Pillow incorrectly handled certain Tiff image files.
If a user or automated system were tricked into opening a specially-crafted
Tiff file, a remote attacker could cause Pillow to crash, resulting in a
denial of service, or possibly execute arbitrary code. (CVE-2021-25290)

It was discovered that Pillow incorrectly handled certain PDF files. If a
user or automated system were tricked into opening a specially-crafted
PDF file, a remote attacker could cause Pillow to hang, resulting in a
denial of service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04
LTS, and Ubuntu 20.10. (CVE-2021-25292)

It was discovered that Pillow incorrectly handled certain SGI image files.
If a user or automated system were tricked into opening a specially-crafted
SGI file, a remote attacker could possibly cause Pillow to crash,
resulting in a denial of service. This issue only affected Ubuntu 18.04
LTS, Ubuntu 20.04 LTS, and Ubuntu 20.10. (CVE-2021-25293)

Jiayi Lin, Luke Shaffer, Xinran Xie, and Akshay Ajayan discovered that
Pillow incorrectly handled certain BLP files. If a user or automated system
were tricked into opening a specially-crafted BLP file, a remote attacker
could possibly cause Pillow to consume resources, resulting in a denial of
service. This issue only affected Ubuntu 18.04 LTS, Ubuntu 20.04 LTS, and
Ubuntu 20.10. (CVE-2021-27921)

Jiayi Lin, Luke Shaffer, Xinran Xie, and Akshay Ajayan discovered that
Pillow incorrectly handled certain ICNS files. If a user or automated
system were tricked into opening a specially-crafted ICNS file, a remote
attacker could possibly cause Pillow to consume resources, resulting in a
denial of service. (CVE-2021-27922)

Jiayi Lin, Luke Shaffer, Xinran Xie, and Akshay Ajayan discovered that
Pillow incorrectly handled certain ICO files. If a user or automated
system were tricked into opening a specially-crafted ICO file, a remote
attacker could possibly cause Pillow to consume resources, resulting in a
denial of service. (CVE-2021-27922)

Update instructions:

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

Ubuntu 20.10:
  python3-pil                     7.2.0-1ubuntu0.2

Ubuntu 20.04 LTS:
  python3-pil                     7.0.0-4ubuntu0.3

Ubuntu 18.04 LTS:
  python-pil                      5.1.0-1ubuntu0.5
  python3-pil                     5.1.0-1ubuntu0.5

Ubuntu 16.04 LTS:
  python-pil                      3.1.2-0ubuntu1.6
  python3-pil                     3.1.2-0ubuntu1.6

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

References:
  https://ubuntu.com/security/notices/USN-4763-1
  CVE-2021-25289, CVE-2021-25290, CVE-2021-25291, CVE-2021-25292,
  CVE-2021-25293, CVE-2021-27921, CVE-2021-27922, CVE-2021-27923

Package Information:
  https://launchpad.net/ubuntu/+source/pillow/7.2.0-1ubuntu0.2
  https://launchpad.net/ubuntu/+source/pillow/7.0.0-4ubuntu0.3
  https://launchpad.net/ubuntu/+source/pillow/5.1.0-1ubuntu0.5
  https://launchpad.net/ubuntu/+source/pillow/3.1.2-0ubuntu1.6