The Linux kernel through 5.3.13 has a start_offset+size Integer Overflow in cpia2_remap_buffer in drivers/media/usb/cpia2/cpia2_core.c because cpia2 has its own mmap implementation. This allows local users (with /dev/video0 access) to obtain read and write permissions on kernel physical pages, which can possibly result in a privilege escalation.
The product performs a calculation that can produce an integer overflow or wraparound when the logic assumes that the resulting value will always be larger than the original value. This occurs when an integer value is incremented to a value that is too large to store in the associated representation. When this occurs, the value may become a very small or negative number.
| Link | Tags |
|---|---|
| https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/log/drivers/media/usb/cpia2/cpia2_core.c | vendor advisory |
| https://deshal3v.github.io/blog/kernel-research/mmap_exploitation | third party advisory exploit |
| https://security.netapp.com/advisory/ntap-20200103-0001/ | third party advisory |
| https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=be83bbf806822b1b89e0a0f23cd87cddc409e429 | vendor advisory |