Buffer overflow in the bufprint function in capiutil.c in libcapi, as used in Linux kernel 2.6.9 to 2.6.20 and isdn4k-utils, allows local users to cause a denial of service (crash) and possibly gain privileges via a crafted CAPI packet.
The product performs operations on a memory buffer, but it reads from or writes to a memory location outside the buffer's intended boundary. This may result in read or write operations on unexpected memory locations that could be linked to other variables, data structures, or internal program data.