==========================================================================
Ubuntu Security Notice USN-8399-1
June 08, 2026

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

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

- Ubuntu 26.04 LTS
- Ubuntu 25.10
- Ubuntu 24.04 LTS
- Ubuntu 22.04 LTS

Summary:

Several security issues were fixed in Pillow.

Software Description:
- pillow: Python Imaging Library

Details:

It was discovered that Pillow incorrectly handled large glyph advance
values in fonts. An attacker could possibly use this issue to cause Pillow
to crash, resulting in a denial of service. (CVE-2026-42308)

It was discovered that Pillow incorrectly handled nested coordinate lists
in certain APIs. An attacker could possibly use this issue to cause Pillow
to crash, resulting in a denial of service. This issue only affected Ubuntu
25.10 and Ubuntu 26.04 LTS. (CVE-2026-42309)

It was discovered that Pillow incorrectly handled certain malformed PDF
files. An attacker could possibly use this issue to cause Pillow to use
excessive resources, leading to a denial of service. (CVE-2026-42310)

It was discovered that Pillow incorrectly handled certain malformed PSD
files. An attacker could possibly use this issue to cause Pillow to crash,
resulting in a denial of service, or to execute arbitrary code. This issue
only affected Ubuntu 25.10 and Ubuntu 26.04 LTS. (CVE-2026-42311)

Update instructions:

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

Ubuntu 26.04 LTS
  python3-pil                     12.1.1-2ubuntu1.2

Ubuntu 25.10
  python3-pil                     11.3.0-1ubuntu1.3

Ubuntu 24.04 LTS
  python3-pil                     10.2.0-1ubuntu1.2

Ubuntu 22.04 LTS
  python3-pil                     9.0.1-1ubuntu0.4

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

References:
  https://ubuntu.com/security/notices/USN-8399-1
  CVE-2026-42308, CVE-2026-42309, CVE-2026-42310, CVE-2026-42311

Package Information:
  https://launchpad.net/ubuntu/+source/pillow/12.1.1-2ubuntu1.2
  https://launchpad.net/ubuntu/+source/pillow/11.3.0-1ubuntu1.3
  https://launchpad.net/ubuntu/+source/pillow/10.2.0-1ubuntu1.2
  https://launchpad.net/ubuntu/+source/pillow/9.0.1-1ubuntu0.4