Malicious PDF — malware analysis report

Static analysis result for SHA-256 73bc30616e1e9752…

MALICIOUS

PDF

66.8 KB Created: 2020-12-21 12:50:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 531018dfade86ed4dc6d58e69f0ef4e3 SHA-1: 78b39fcdaa2557d9f72ea6b7636a1e5885976764 SHA-256: 73bc30616e1e9752d32ed59943ebb09f6b5baf650fa2b7e9d775f2e9d7e32a51
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics, including ClamAV and an ML classifier, indicating malicious intent. The presence of a PDF link farm heuristic and numerous external URLs suggests a phishing or SEO manipulation scheme. While no scripts were explicitly extracted, the PDF format can embed JavaScript, and the overall structure points towards a malicious document designed to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://traffset.ru/123?utm_term=what+are+elements+compounds+and+mixtures+in+science
    • https://vakogupomuniv.weebly.com/uploads/1/3/4/6/134610568/zagezirira_tawug.pdf
    • https://cdn-cms.f-static.net/uploads/4371509/normal_5fd648bab70a1.pdf
    • https://cdn-cms.f-static.net/uploads/4417129/normal_5f98302d3cef4.pdf
    • https://static.s123-cdn-static.com/uploads/4410206/normal_5fdeae030c3b3.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/rodigapigeta/kijomezo.pdf
    • https://uploads.strikinglycdn.com/files/d27748a5-168d-49c4-8d2d-2c5de3d7858f/snes_star_fox_2_rom.pdf
    • https://uploads.strikinglycdn.com/files/75e85bfc-b3ee-4e1d-90a6-f8f63a41ab3e/la_guerre_de_troie.pdf
    • https://s3.amazonaws.com/petubapizo/55407176132.pdf
    • https://uploads.strikinglycdn.com/files/1108ff53-928d-400c-a8b9-fc65d05b1cf1/xorugor.pdf
    • https://uploads.strikinglycdn.com/files/21c42e92-7f12-4176-9cad-5b065ba8f98d/ropigilaxaguvugexipanul.pdf
    • https://s3.amazonaws.com/nimuwet/bhu_bsc_math_syllabus.pdf
    • https://uploads.strikinglycdn.com/files/cc23f881-eefa-4d3c-8ae1-3245e0180acc/37324647644.pdf
    • https://s3.amazonaws.com/suzixegazunow/grade_10_math_answer_key_unit_4.pdf
    • https://uploads.strikinglycdn.com/files/8597d2a4-113d-40ad-9c03-098a87635862/52680672040.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c8f3.bin
83d787e1ec14117d441ee8133039f7ae40014136192d74a85fc2d8d9040c9540
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8F3 5396 bytes
font_01_sfnt_off0000db2c.bin
5d41f185a24576dec79d93545536e2dad37dcb090b98394050d32b67b5c091ea
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB2C 10248 bytes