High [CVE-2026-54060] Denial of Service via excessive memory allocation when processing font files

Pillow is a Python imaging library. Prior to 12.3.0, PIL/FontFile.py FontFile.compile() assembled per-glyph images into a combined bitmap with Image.new("1", (xsize, ysize)) without calling Image._decompression_bomb_check(), allowing a font to trigger excessive allocation during conversion or saving.

This issue is fixed in version 12.3.0. When processing a specially crafted font file, the library's font compilation function does not adequately check for excessive memory allocation.

This oversight allows a remote attacker to trigger an unreasonable consumption of system memory, leading to a denial of service (DoS) for the application. A flaw was found in Pillow prior to version 12.3.0.

This allows a specially crafted font file to trigger excessive memory allocation during conversion or saving, leading to denial of service via resource exhaustion. Red Hat severity: Important — CVSS 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H).

Weakness: CWE-1050.

Affected products named by the advisory: Red Hat Ansible Automation Platform 2.5 for RHEL 8; Red Hat Ansible Automation Platform 2.5 for RHEL 9; Red Hat Ansible Automation Platform 2.6 for RHEL 9; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support; and 28 more.