CVE-2025-40322: Linux

High severity, CVSS 7.1. EPSS: 0.1% chance of exploitation in the next 30 days.

In the Linux kernel, the following vulnerability has been resolved: fbdev: bitblit: bound-check glyph index in bit_putcs* bit_putcs_aligned()/unaligned() derived the glyph pointer from the character value masked by 0xff/0x1ff, which may exceed the actual font's glyph count and read past the end of the built-in font array. Clamp the index to the actual glyph count before computing the address. This fixes a global out-of-bounds read reported by syzbot.

Affected products

• Linux Linux: from 2.6.12, before 5.4.302 (fixed in 5.4.302); from 5.5, before 5.10.247 (fixed in 5.10.247); from 5.11, before 5.15.197 (fixed in 5.15.197); from 5.16, before 6.1.159 (fixed in 6.1.159); from 6.2, before 6.6.117 (fixed in 6.6.117); from 6.7, before 6.12.58 (fixed in 6.12.58); …

Published 2025-12-08. Last modified 2026-07-30.