fbdev: bitblit: bound-check glyph index in bit_putcs*
21Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 7.1epss 0.1%
exploitation probability
0.1%top 96% of all CVEs
observed exploitation
nono source reports it
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.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
Affected products
Linux · LinuxReferences
https://git.kernel.org/stable/c/0998a6cb232674408a03e8561dc15aa266b2f53bhttps://git.kernel.org/stable/c/18c4ef4e765a798b47980555ed665d78b71aeadfhttps://git.kernel.org/stable/c/901f44227072be60812fe8083e83e1533c04eed1https://git.kernel.org/stable/c/9ba1a7802ca9a2590cef95b253e6526f4364477fhttps://git.kernel.org/stable/c/a10cede006f9614b465cf25609a8753efbfd45cchttps://git.kernel.org/stable/c/c12003bf91fdff381c55ef54fef3e961a5af2545https://git.kernel.org/stable/c/db5c9a162d2f42bcc842b76b3d935dcc050a0eechttps://git.kernel.org/stable/c/efaf89a75a29b2d179bf4fe63ca62852e93ad620