CVE-2025-39967
Gravedad:
Pendiente de análisis
Tipo:
No Disponible / Otro tipo
Fecha de publicación:
15/10/2025
Última modificación:
16/10/2025
Descripción
*** Pendiente de traducción *** In the Linux kernel, the following vulnerability has been resolved:<br />
<br />
fbcon: fix integer overflow in fbcon_do_set_font<br />
<br />
Fix integer overflow vulnerabilities in fbcon_do_set_font() where font<br />
size calculations could overflow when handling user-controlled font<br />
parameters.<br />
<br />
The vulnerabilities occur when:<br />
1. CALC_FONTSZ(h, pitch, charcount) performs h * pith * charcount<br />
multiplication with user-controlled values that can overflow.<br />
2. FONT_EXTRA_WORDS * sizeof(int) + size addition can also overflow<br />
3. This results in smaller allocations than expected, leading to buffer<br />
overflows during font data copying.<br />
<br />
Add explicit overflow checking using check_mul_overflow() and<br />
check_add_overflow() kernel helpers to safety validate all size<br />
calculations before allocation.
Impacto
Referencias a soluciones, herramientas e información
- https://git.kernel.org/stable/c/1a194e6c8e1ee745e914b0b7f50fa86c89ed13fe
- https://git.kernel.org/stable/c/4a4bac869560f943edbe3c2b032062f6673b13d3
- https://git.kernel.org/stable/c/994bdc2d23c79087fbf7dcd9544454e8ebcef877
- https://git.kernel.org/stable/c/9c8ec14075c5317edd6b242f1be8167aa1e4e333
- https://git.kernel.org/stable/c/a6eb9f423b3db000aaedf83367b8539f6b72dcfc
- https://git.kernel.org/stable/c/adac90bb1aaf45ca66f9db8ac100be16750ace78
- https://git.kernel.org/stable/c/b8a6e85328aeb9881531dbe89bcd2637a06c3c95
- https://git.kernel.org/stable/c/c0c01f9aa08c8e10e10e8c9ebb5be01a4eff6eb7



