Malicious PDF — malware analysis report

Static analysis result for SHA-256 daf8d499e0e20741…

MALICIOUS

PDF

140.2 KB
MD5: 199cf4018eae0a7376ac576b13d1c400 SHA-1: a764db43e98a098ed2fecde27bcff3fcb9314892 SHA-256: daf8d499e0e207416c985a8803517bdda77e8ce9e16a43523bbb8d4772eac76d
562 Risk Score

Malware Insights

MITRE ATT&CK
T1204.002 Malicious File T1059.003 Windows Command Shell T1105 Ingress Tool Transfer T1204.001 User Execution: Malicious Link T1566.001 Phishing: Spearphishing Attachment

The PDF file contains embedded JavaScript and a launch action that targets cmd.exe, indicating an attempt to execute arbitrary commands. Critical heuristics confirm this, specifically CVE_2010_1240, which points to Adobe Reader launch action command execution. Furthermore, an embedded Windows executable payload was detected, masquerading as 'test.pdf', and ClamAV identified it as 'Win.Trojan.MSShellcode-7'. The overall behavior suggests a dropper mechanism designed to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9999

Heuristics 14

  • Adobe Reader Launch action command execution critical CVE exact CVE_2010_1240
    PDF uses the Adobe Reader/Acrobat Launch action pattern associated with CVE-2010-1240: cmd.exe is invoked with attacker-controlled parameters, paired with an embedded/exported payload.
  • Launch action critical PDF_LAUNCH
    PDF contains a /Launch action whose target is an executable, URL, or UNC path — can start an external application
  • Embedded Windows executable payload in PDF stream critical PDF_EMBEDDED_PE_PAYLOAD
    PDF stream bytes contain an embedded Windows executable with a verified PE header. Exploit chains often hide droppers inside ordinary streams rather than standard /EmbeddedFile attachments.
  • /Launch action target: cmd.exe critical PDF_LAUNCH_COMMAND
    PDF /Launch action specifies an executable target with parameters '/Q /C %HOMEDRIVE%&cd %HOMEPATH%&(if exist "Desktop\\test.pdf" (cd "Desktop"' — references a known-dangerous executable (cmd, PowerShell, etc.).
  • Embedded attachment masquerades: declared document, content is windows-executable critical PDF_EMBEDDED_FILESPEC_CONTENT_MISMATCH
    An /EmbeddedFile attachment's declared filename extension or /Subtype MIME type contradicts the magic bytes of its decompressed content. The attachment is declared as a benign document or image but the bytes are an executable or executable-bearing archive. This is a deliberate deception used to hide droppers in PDF attachments and is a generic indicator of embed-and-drop weaponisation, independent of any specific CVE.
  • ClamAV: Pdf.Tool.Agent-1388586 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Tool.Agent-1388586
  • ClamAV detection on extracted artifact critical EXTRACTED_FILE_CLAMAV
    ClamAV flagged at least one file extracted from inside this sample. Even when the wrapping document carries no AV detection of its own, a hit on the carved artifact is a strong indicator the sample is a delivery vehicle.
  • /Launch action paired with attachment-dropping JS API high PDF_LAUNCH_PLUS_DROPPER_JS
    PDF combines a /Launch action with a JavaScript API call that writes or opens an attached/external resource — the canonical shape of the CVE-2010-1240 /Launch + exportDataObject family. Benign PDFs do not pair these surfaces; the combination indicates a drop-and-execute chain regardless of the specific JS API knobs or /Launch target.
  • Clickable PDF combines external action with parser-evasion structure high PDF_ACTION_PARSER_EVASION
    PDF has an external clickable URI together with object graph or xref structures that make parsers disagree, such as divergent duplicate objects, parser divergence, or xref offset mismatch. That combination is stronger than a plain link: the document is both an outward-action carrier and a parser-confusion/evasion sample.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Embedded file low PDF_EMBEDDED
    PDF embeds a file attachment — could carry an executable or another weaponised document as a nested payload
  • External URI low PDF_URI
    PDF contains an external URL action
  • 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://www.afterdawn.com/glossary/terms/conditional_access_module.cfm
    • http://www.afterdawn.com/glossary/terms/conditional_access_system.cfm

Extracted artifacts 7

Files carved from inside the sample during analysis.

FilenameKindSourceSize
test.pdf
b85f240d8964eda2cd82ef52ee4d8f428b2c5cec0340ac0499c7203044c6b0bf
pdf-embedded-file PDF EmbeddedFile object 52 at offset 0x18031 73802 bytes
Detection
ClamAV: Win.Trojan.MSShellcode-7
Obfuscation or payload: unlikely
javascript_obj0053_000.js
b1a09f919e0f5d1c1d284849c9af93bae6fd1411634dfdc491e126f9cd327f3f
pdf-javascript-stream PDF /JS object 53 at offset 0x22CB3 53 bytes
stream_007_off0000d99c.bin
7af40e8778d002cc3fc1564a190e9d8643f068cefd9cf1da8934adac4b2837f7
decompressed-pdf-stream PDF FlateDecoded stream at offset 0xD99C 28748 bytes
icc_00_off0000b62a.icc
2b3aa1645779a9e634744faf9b01e9102b0c9b88fd6deced7934df86b949af7e
pdf-icc-profile PDF ICC profile at offset 0xB62A 3144 bytes
icc_01_off0000c0ff.icc
bad673993556e6b0887d39ea77607649277a6ccaa6a2d454ec077dad52adc122
pdf-icc-profile PDF ICC profile at offset 0xC0FF 4380 bytes
font_01_sfnt_off00012d08.bin
6e28b485e52e02cd3776de5f6910482cd52337d749fddb0c950b554f588e8167
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D08 6780 bytes
font_02_sfnt_off000141cf.bin
918283255c3352ee70016b40338614216d29cc719387b49bfbfecb255d021109
pdf-font-stream PDF embedded font (sfnt) at offset 0x141CF 19520 bytes