cbcvebase.
CVE-2019-8042
published 2019-08-20

CVE-2019-8042: Adobe Acrobat and Reader versions 2019.012.20035 and earlier, 2019.012.20035 and earlier, 2017.011.30142 and earlier, 2017.011.30143 and earlier…

PriorityP267critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EXPLOIT
EPSS
16.84%
96.7th percentile
Adobe Acrobat and Reader versions 2019.012.20035 and earlier, 2019.012.20035 and earlier, 2017.011.30142 and earlier, 2017.011.30143 and earlier, 2015.006.30497 and earlier, and 2015.006.30498 and earlier have a heap overflow vulnerability. Successful exploitation could lead to arbitrary code execution .

Affected

7 ranges
VendorProductVersion rangeFixed in
adobeacrobat_dc>= 15.006.30060 < 15.006.3049915.006.30499
adobeacrobat_dc>= 15.008.20082 < 19.012.2003619.012.20036
adobeacrobat_dc>= 17.011.30059 < 17.011.3014417.011.30144
adobeacrobat_reader_dc>= 15.006.30060 < 15.006.3049915.006.30499
adobeacrobat_reader_dc>= 15.008.20082 < 19.012.2003619.012.20036
adobeacrobat_reader_dc>= 17.011.30059 < 17.011.3014417.011.30144
adobeadobe_acrobat_and_reader

Detection & IOCsextracted from sources · hover to see the quote

urlhttps://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/47276.zip
urlhttps://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/47769.zip
bytes
0x2bd4c: 0x00 => 0xff, 0x2bd4d: 0x00 => 0xff, 0x2d5b8: 0x00 => 0xff
  • Crash triggered immediately upon opening a malformed PDF containing a crafted TrueType font (TTF) stream; monitor AcroRd32/Acrobat for access violation (code c0000005) originating from CoolType.dll during PDF open events.
  • Look for heap-based out-of-bounds write in CoolType.dll (CTInit function) triggered by a malformed TTF font embedded in a PDF; the write occurs at a large negative offset from the heap allocation base.
  • Mutation of three specific bytes inside a TrueType font stream embedded in a PDF (offsets 0x2bd4c, 0x2bd4d, 0x2d5b8 changed from 0x00 to 0xff) is sufficient to trigger the vulnerability; YARA rules targeting 0xff bytes at these offsets within a TTF stream in PDF may aid detection.
  • Affected version confirmed as Adobe Acrobat Reader DC 2019.012.20035 on Windows 10; presence of this version combined with PDF-triggered CoolType crash is a strong indicator of exploitation attempt.
  • ·A second, nearly identical crash was observed in version 2019.012.20040 (after the CVE-2019-8042 patch), suggesting an incomplete fix or variant; detections targeting only the patched version boundary may miss this follow-on issue.
  • ·The heap corruption is more cleanly observable with Windows PageHeap (gflags) enabled; without PageHeap the crash may be less deterministic and harder to reproduce in standard monitoring environments.

CVSS provenance

nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.5HIGHAV:N/AC:L/Au:N/C:P/I:P/A:P
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