Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a4cdcf05d455870…

MALICIOUS

PDF

6.3 KB Created: 2010-08-29 16:19:36 Authoring application: styeZek colSnap
MD5: b943082c5fa88514d791dfc0b7795644 SHA-1: a245d396b6f6eba0d5a3cdc6133a0171a0b38d63 SHA-256: 4a4cdcf05d4558704567764639cd8e74f4e2eeba428b7f1d7eae18fbcef2b299
246 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.001 PowerShell

The sample is a PDF document that exploits CVE-2010-0188, a known vulnerability in Adobe Reader related to XFA forms. The heuristic firings indicate the presence of an embedded script payload and an eval() call, strongly suggesting that the exploit is used to download and execute a secondary payload. The document body is heavily obfuscated and unreadable, providing no direct clues about the lure, but the exploit and embedded script are sufficient indicators of malicious intent.

Heuristics 10

  • Adobe Reader LibTIFF XFA image exploit — CVE-2010-0188 critical CVE likely CVE_2010_0188
    PDF contains the CVE-2010-0188 exploit template: XFA JavaScript heap-spray setup, a generated TIFF image payload, and assignment of that TIFF data to an XFA image field rawValue to trigger Adobe Reader's LibTIFF parser.
  • XFA form contains executable script high CVE related PDF_XFA_SCRIPT
    PDF embeds an XFA form whose dataset contains a <script> or <xfa:script> block — XFA scripting has been the exploit primitive for several Adobe Reader RCEs (CVE-2010-0188 family, CVE-2018-4901, and others). Plain XFA without scripts is far less risky.
  • ClamAV: Pdf.Exploit.Dropped-81 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Exploit.Dropped-81
  • eval() call high PDF_EVAL
    eval() found — commonly used for obfuscated exploit execution
  • Embedded script payload in PDF stream medium PDF_EMBEDDED_SCRIPT_PAYLOAD
    PDF stream bytes contain an HTML/XFA <script> tag without accompanying Windows shell-execution primitives — common in accessible XFA forms but worth surfacing for analyst review.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • XFA form low PDF_XFA
    PDF uses XML Forms Architecture — can contain script logic
  • String.fromCharCode low PDF_FROMCHARCODE
    String.fromCharCode found — used to construct payload strings dynamically. Common in benign JavaScript libraries for codepoint manipulation, so this alone is informational; weaponised use is also caught by the dedicated fromCharCode-stage and exploit-shape rules. (matched inside decoded stream)
  • Suspicious extracted artifact info EXTRACTED_FILE_STATIC_TRIAGE
    One or more files extracted from inside this sample matched static suspicious-content checks such as script obfuscation, encoded payload blobs, packed data, or execution/download terms.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://ns.adobe.com/xdp/
    • http://www.xfa.org/schema/xci/1.0/
    • http://www.xfa.org/schema/xfa-template/2.5/
    • http://ns.adobe.com/xtd/
    • http://ns.adobe.com/xfdf/
    • http://www.xfa.org/schema/xfa-form/2.8/

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
embedded_file_obj0008.bin
78f9631071f03cd2eafd8de565f399d0c62edde5175ed6f90c6215135b7f3b76
pdf-embedded-file PDF EmbeddedFile object 8 at offset 0xDB 134 bytes
embedded_file_obj0010.bin
d4ff871de6628873a7035e48c3dfa9affd8413c4e514b4f2b79a912efb0ddaf9
pdf-embedded-file PDF EmbeddedFile object 10 at offset 0x1AA 712 bytes
embedded_file_obj0011.bin
469f65eb99ed3809391ed31b4c46774247932afef26b4aa10a5a48fbcd239359
pdf-embedded-file PDF EmbeddedFile object 11 at offset 0x4BD 433 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0012.bin
103d1e7983cf88bfacedddb4af33ffb5317d9c2c8b3e1bfd987b2c5d712bc985
pdf-embedded-file PDF EmbeddedFile object 12 at offset 0x6B9 323 bytes
embedded_file_obj0014.bin
a947d7ab6fc467be9d3b3da81d28de7dd1c2ae2771215e4a327e6a38839a2a0e
pdf-embedded-file PDF EmbeddedFile object 14 at offset 0x85A 12272 bytes
Detection
ClamAV: No threats found
Obfuscation or payload: likely
Carved artifact contains 1 eval/decoder/string-building token(s).
embedded_file_obj0015.bin
e6c26a3478346d27e841ad49868ebf68bf4c6863b6750e8d60bda3c4c6f79876
pdf-embedded-file PDF EmbeddedFile object 15 at offset 0x14EC 77 bytes
embedded_file_obj0016.bin
92a3ce61d783e15932b5de127ce45a9b4c2f98f4da2453f65241573c1dda808a
pdf-embedded-file PDF EmbeddedFile object 16 at offset 0x1580 56 bytes