Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b73433d499db19d…

MALICIOUS

PDF

68.3 KB Created: 2021-02-24 06:44:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-29
MD5: be6e3fc2cee117a30edde06b479517a1 SHA-1: 4afe5ed5648f2cda13ac40ad8117ee3aaf0efcd0 SHA-256: 7b73433d499db19deaadc24831ee25f97c338b6a9f80210472caf967a7b60369
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many of which are dynamically generated or use keywords, indicating a link farm or SEO spam tactic. The ML classifier strongly flagged this PDF as malicious, and the presence of embedded URLs further supports malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external links suggest it's designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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 https://druttle.ru/wix?keyword=tekken+tag+tournament+2+guide+pdf PDF link annotation
    • https://filududo.weebly.com/uploads/1/3/5/3/135390237/5312468.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4484169/normal_5feda216cbb45.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4418399/normal_60303084a3a2d.pdfIn PDF document text
    • https://cdn.sqhk.co/ditetona/PwYejia/best_music_player_program_for_windows_10.pdfIn PDF document text
    • https://dagatofolake.weebly.com/uploads/1/3/0/8/130874029/jurip.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4407729/normal_600bdfaa6a943.pdfIn PDF document text
    • http://unosital.space/4934837781248na.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/jebupofedijakuk/waduzumogobisup.pdfIn PDF document text
    • https://s3.amazonaws.com/remufuzu/2305376474.pdfIn PDF document text
    • https://s3.amazonaws.com/duzexefemosaxe/79474170954.pdfIn PDF document text
    • http://judewal.rf.gd/89409848719.pdfIn PDF document text
    • http://mimewimirul.rf.gd/zemidusizolapobe.pdfIn PDF document text
    • https://s3.amazonaws.com/vojapu/tv_guide_sky_sports_f1.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cf7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF7D 5296 bytes
SHA-256: a1a47da8afb1ae80b0f1ce528dc38038556ba3c3f0378d8526b64f68824b2e7d
font_01_sfnt_off0000e176.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE176 10228 bytes
SHA-256: 6bf1098a38469d6e31cbc49e3864a2def7b9d1eedfeab7edd6885fc690026d18