Nothings stb stb_vorbis.c setup_free allocation of resources

A vulnerability was identified in Nothings stb up to 1.22. The impacted element is the function setup_free of the file stb_vorbis.c. The manipulation leads to allocation of resources. The attack is possible to be carried out remotely. The exploit is publicly available and might be used. The vendor was contacted early about this disclosure but did not respond in any way.

Nothings stb stb_vorbis.c start_decoder out-of-bounds write

A security flaw has been discovered in Nothings stb up to 1.22. This affects the function start_decoder of the file stb_vorbis.c. The manipulation results in out-of-bounds write. The attack may be performed from remote. The exploit has been released to the public and may be used for attacks. The vendor was contacted early about this disclosure but did not respond in any way.

A heap-based buffer overflow vulnerability exists in the comment functionality of stb _vorbis.c v1.22. A specially crafted .ogg file can lead to an out-of-bounds write. An attacker can provide a malicious file to trigger this vulnerability.

Out of bounds heap buffer write in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger memory write past an allocated heap buffer in `start_decoder`. The root cause is a potential integer overflow in `sizeof(char*) * (f->comment_list_length)` which may make `setup_malloc` allocate less memory than required. Since there is another integer overflow an attacker may overflow it too to force `setup_malloc` to return 0 and make the exploit more reliable. This issue may lead to code execution.

0 byte write heap buffer overflow in start_decoder in stb_vorbis

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.

Wild address read in vorbis_decode_packet_rest in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger out of bounds read in `DECODE` macro when `var` is negative. As it can be seen in the definition of `DECODE_RAW` a negative `var` is a valid value. This issue may be used to leak internal memory allocation information.

Null pointer dereference in vorbis_deinit in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger memory allocation failure in `start_decoder`. In that case the function returns early, the `f->comment_list` is set to `NULL`, but `f->comment_list_length` is not reset. Later in `vorbis_deinit` it tries to dereference the `NULL` pointer. This issue may lead to denial of service.

Attempt to free an uninitialized memory pointer in vorbis_deinit in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger memory allocation failure in `start_decoder`. In that case the function returns early, but some of the pointers in `f->comment_list` are left initialized and later `setup_free` is called on these pointers in `vorbis_deinit`. This issue may lead to code execution.

Off-by-one heap buffer write in start_decoder in stb_vorbis

stb_vorbis is a single file MIT licensed library for processing ogg vorbis files. A crafted file may trigger out of buffer write in `start_decoder` because at maximum `m->submaps` can be 16 but `submap_floor` and `submap_residue` are declared as arrays of 15 elements. This issue may lead to code execution.

Heap buffer out of bounds write in start_decoder in stb_vorbis

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 `len` read in `start_decoder` is a negative number and `setup_malloc` successfully allocates memory in that case, but memory write is done with a negative index `len`. Similarly if len is INT_MAX the integer overflow len+1 happens in `f->vendor = (char*)setup_malloc(f, sizeof(char) * (len+1));` and `f->comment_list[i] = (char*)setup_malloc(f, sizeof(char) * (len+1));`. This issue may lead to code execution.

Multi-byte write heap buffer overflow in start_decoder in stb_vorbis

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[i] = get8_packet(f);`. The root cause is an integer overflow in `setup_malloc`. A sufficiently large value in the variable `sz` overflows with `sz+7` in and the negative value passes the maximum available memory buffer check. This issue may lead to code execution.