CVE-2017-9995 (published 2017-06-28T06:29Z)

libavcodec/scpr.c in FFmpeg 3.3 before 3.3.1 does not properly validate height and width data, which allows remote attackers to cause a denial of service (heap-based buffer overflow and application crash) or possibly have unspecified other impact via a crafted file.

Severity: MEDIUM
CVSS v2 base score: 6.8 (AV:N/AC:M/Au:N/C:P/I:P/A:P)
CVSS v3 base score: 7.8, HIGH (CVSS:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H)

Weakness information:
cwe_id: CWE-119
cwe_name: Improper Restriction of Operations within the Bounds of a Memory Buffer
description: 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.
extended_description: 
            Certain languages allow direct addressing of memory locations and do not automatically ensure that these locations are valid for the memory buffer that is being referenced. This can cause read or write operations to be performed on memory locations that may be associated with other variables, data structures, or internal program data.
         
         

Fix information:
repo_url: https://github.com/FFmpeg/FFmpeg
commit_details: repo_url: https://github.com/FFmpeg/FFmpeg
author: Michael Niedermayer
author_date: 2017-05-11 15:29:31+02:00
msg: avcodec/scpr: Check y in first line loop in decompress_i()

Fixes: out of array access
Fixes: 1478/clusterfuzz-testcase-minimized-5285486908145664

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
repository: repo_url: https://github.com/FFmpeg/FFmpeg
repo_name: FFmpeg/FFmpeg
description: Mirror of https://git.ffmpeg.org/ffmpeg.git
repo_language: C
owner: FFmpeg
file_changes: filename: scpr.c
change_type: ModificationType.MODIFY
diff: @@ -331,6 +331,9 @@ static int decompress_i(AVCodecContext *avctx, uint32_t *dst, int linesize)
         clr = (b << 16) + (g << 8) + r;
         k += run;
         while (run-- > 0) {
+            if (y >= avctx->height)
+                return AVERROR_INVALIDDATA;
+
             dst[y * linesize + x] = clr;
             lx = x;
             ly = y;

programming_language: C
repo_url: https://github.com/FFmpeg/FFmpeg
commit_details: repo_url: https://github.com/FFmpeg/FFmpeg
author: Michael Niedermayer
author_date: 2017-05-13 15:39:32+02:00
msg: avcodec/scpr: Fix multiple runtime error: index 256 out of bounds for type 'unsigned int [256]'

Fixes: 1519/clusterfuzz-testcase-minimized-5286680976162816

Found-by: continuous fuzzing process https://github.com/google/oss-fuzz/tree/master/targets/ffmpeg
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>
repository: repo_url: https://github.com/FFmpeg/FFmpeg
repo_name: FFmpeg/FFmpeg
description: Mirror of https://git.ffmpeg.org/ffmpeg.git
repo_language: C
owner: FFmpeg
file_changes: filename: scpr.c
change_type: ModificationType.MODIFY
diff: @@ -261,6 +261,9 @@ static int decode_unit(SCPRContext *s, PixelModel *pixel, unsigned step, unsigne
             break;
         c++;
     }
+    if (x >= 16 || c >= 256) {
+        return AVERROR_INVALIDDATA;
+    }
 
     if ((ret = s->decode(gb, rc, cumfr, cnt_c, totfr)) < 0)
         return ret;

programming_language: C