| Summary: | Heap-Buffer Overflow in SDL_GetRGB pertaining to SDL_pixels.c | ||
|---|---|---|---|
| Product: | SDL | Reporter: | Radue <epitectus.agamemon> |
| Component: | video | Assignee: | Sam Lantinga <slouken> |
| Status: | RESOLVED FIXED | QA Contact: | Sam Lantinga <slouken> |
| Severity: | critical | ||
| Priority: | P2 | CC: | ppisar |
| Version: | HG 2.1 | ||
| Hardware: | x86_64 | ||
| OS: | Linux | ||
| Attachments: | PoC | ||
Created attachment 3605 [details]
PoC
PoC: See attachment Reproducing steps: 1. Download SDL-1.2.15 library 2. ./configure with Asan enabled 3. ./make 4. sudo make install 5. cd examples 6. ./configure with Asan enabled 7. make 8. ./testsprite PoC Assigned CVE-2019-7636 by MITRE. This POC BMP image has invalid number of colors (biClrUsed=3, biBitCount=0). In my case this results into invalid write when parsing the BMP file: ==7124== Invalid write of size 1 ==7124== at 0x483F7B3: memmove (vg_replace_strmem.c:1271) ==7124== by 0x4AE06EA: _IO_file_xsgetn (in /usr/lib64/libc-2.29.so) ==7124== by 0x4AD4FE6: fread (in /usr/lib64/libc-2.29.so) ==7124== by 0x4859F70: stdio_read (SDL_rwops.c:336) ==7124== by 0x487EAF1: SDL_LoadBMP_RW (SDL_bmp.c:246) ==7124== by 0x401359: LoadSprite (testsprite.c:36) ==7124== by 0x401B25: main (testsprite.c:224) In case of the original report, SDL_GetRGB() function reads from fmt->palette->colors[] array that is badly allocated because of the invalid number of colors. A fix for this issue is covered by patch for bug #4500. |
A heap-buffer overflow vulnerability was discovered in SDL-1.2.15 library. Asan report: ================================================================= ==22885==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x60200006b7c8 at pc 0x7ff12191f442 bp 0x7ffc642d4e90 sp 0x7ffc642d4e88 READ of size 1 at 0x60200006b7c8 thread T0 #0 0x7ff12191f441 in SDL_GetRGB /home/radu/apps/sdl_player_lib/SDL-1.2.15/build/../src/video/SDL_pixels.c:416:8 #1 0x7ff12192d2fa in SDL_ConvertSurface /home/radu/apps/sdl_player_lib/SDL-1.2.15/build/../src/video/SDL_surface.c:877:4 #2 0x7ff121932a40 in SDL_DisplayFormat /home/radu/apps/sdl_player_lib/SDL-1.2.15/build/../src/video/SDL_video.c:946:9 #3 0x4dba11 in LoadSprite /home/radu/apps/sdl_player_lib/SDL-1.2.15/test/testsprite.c:41:9 #4 0x4dbc8f in main /home/radu/apps/sdl_player_lib/SDL-1.2.15/test/testsprite.c:98:7 #5 0x7ff12060682f in __libc_start_main /build/glibc-Cl5G7W/glibc-2.23/csu/../csu/libc-start.c:291 #6 0x435528 in _start (/home/radu/apps/sdl_player_lib/SDL-1.2.15/test/testsprite+0x435528) 0x60200006b7c8 is located 8 bytes to the left of 16-byte region [0x60200006b7d0,0x60200006b7e0) freed by thread T0 here: #0 0x4bc212 in __interceptor_free (/home/radu/apps/sdl_player_lib/SDL-1.2.15/test/testsprite+0x4bc212) #1 0x7ff1203c8dc7 (/usr/lib/x86_64-linux-gnu/libxcb.so.1+0xadc7) previously allocated by thread T0 here: #0 0x4bc4f2 in malloc (/home/radu/apps/sdl_player_lib/SDL-1.2.15/test/testsprite+0x4bc4f2) #1 0x7ff1203ca2aa (/usr/lib/x86_64-linux-gnu/libxcb.so.1+0xc2aa) SUMMARY: AddressSanitizer: heap-buffer-overflow /home/radu/apps/sdl_player_lib/SDL-1.2.15/build/../src/video/SDL_pixels.c:416 SDL_GetRGB Shadow bytes around the buggy address: 0x0c04800056a0: fa fa fd fd fa fa fd fd fa fa fd fd fa fa fd fd 0x0c04800056b0: fa fa 00 00 fa fa 00 04 fa fa 00 04 fa fa 00 04 0x0c04800056c0: fa fa 00 04 fa fa 00 04 fa fa 00 04 fa fa 00 04 0x0c04800056d0: fa fa 00 04 fa fa fd fd fa fa fd fd fa fa fd fd 0x0c04800056e0: fa fa fd fd fa fa fd fd fa fa fd fd fa fa fd fd =>0x0c04800056f0: fa fa fd fd fa fa fd fd fa[fa]fd fd fa fa fd fd 0x0c0480005700: fa fa fd fd fa fa fd fd fa fa fd fd fa fa fd fd 0x0c0480005710: fa fa fd fd fa fa fd fd fa fa fd fd fa fa fd fd 0x0c0480005720: fa fa fd fd fa fa fd fd fa fa fd fd fa fa fd fd 0x0c0480005730: fa fa fd fd fa fa 00 fa fa fa 00 00 fa fa fd fd 0x0c0480005740: fa fa fd fd fa fa fd fd fa fa 07 fa fa fa fd fd Shadow byte legend (one shadow byte represents 8 application bytes): Addressable: 00 Partially addressable: 01 02 03 04 05 06 07 Heap left redzone: fa Heap right redzone: fb Freed heap region: fd Stack left redzone: f1 Stack mid redzone: f2 Stack right redzone: f3 Stack partial redzone: f4 Stack after return: f5 Stack use after scope: f8 Global redzone: f9 Global init order: f6 Poisoned by user: f7 Container overflow: fc Array cookie: ac Intra object redzone: bb ASan internal: fe Left alloca redzone: ca Right alloca redzone: cb ==22885==ABORTING