Malicious PDF — malware analysis report

Static analysis result for SHA-256 b98875ac5c74c10f…

MALICIOUS

PDF

44.0 KB Created: 2020-04-10 03:09:17 +03:00 Authoring application: wkhtmltopdf 0.12.1.4 (via Qt 4.8.6) First seen: 2020-09-24
MD5: 02a717ccf720702718182c7d15653732 SHA-1: d092c3caa49cfbf76bfd2cb7b9a04a674b2b00a3 SHA-256: b98875ac5c74c10f9db68918e46687c8692f9d51536d48276f5fd59c7b4a4106
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains a significant number of external links to various domains, identified by the PDF_SEO_LINK_FARM heuristic. The ML classifier also strongly indicated maliciousness. The embedded URLs likely serve to redirect users to potentially malicious content or to manipulate search engine rankings. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://wolfecityhomecoming.com/uploads/1/3/0/2/130287242/130287242.html#natural+language+processing+with+pyt PDF link annotation
    • http://44michigan.com/uploads/1/3/1/3/131378835/15359d0b40.pdfIn PDF document text
    • http://filmnedit.com/uploads/1/3/0/9/130969198/voxuxixetupeve.pdfIn PDF document text
    • http://awocdocos.com/uploads/1/3/1/6/131607230/jiwizaxeravujupotusu.pdfIn PDF document text
    • http://polliteracy.com/uploads/1/3/0/5/130589195/juzoxubadumu-jarebudetijuveg-zuravagagu.pdfIn PDF document text
    • http://amandajoysmusic.com/uploads/1/3/1/4/131406343/vomav-mivesi-zefalalotaza.pdfIn PDF document text
    • http://rekapltd.com/uploads/1/3/1/4/131437603/ruvakuseposara.pdfIn PDF document text
    • http://pennyasornberger.com/uploads/1/3/0/8/130813904/148786.pdfIn PDF document text
    • http://thescholarshipblueprint.com/uploads/1/3/1/3/131378796/23e22c.pdfIn PDF document text
    • http://tjhalliday.com/uploads/1/3/1/4/131438164/2450902.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006e43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6E43 8384 bytes
SHA-256: 5bf60a019ba5291cc5850d1d37223bbedfd3c31aeb2b7ac0d97eca1a6a7a7186
font_01_sfnt_off00008e2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8E2D 16076 bytes
SHA-256: 0d5d1431431a9f8dc10f3748659f3927b3f3a14b81a73ef3b8e9723c206f5964