stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger out of bounds write in `f->vendor[len] = (char)\'\0\';`. The root cause is that if the len read in `start_decoder` is `-1` and `len + 1` becomes 0 when passed to `setup_malloc`. The `setup_malloc` behaves differently when `f->alloc.alloc_buffer` is pre-allocated. Instead of returning `NULL` as in `malloc` case it shifts the pre-allocated buffer by zero and returns the currently available memory block. This issue may lead to code execution.
Metrics
CVSS Version: 3.1 |
Base Score: 6.5 MEDIUM Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L