Malicious PDF — malware analysis report

Static analysis result for SHA-256 bd85bbc8cbb7a381…

MALICIOUS

PDF

66.9 KB Created: 2020-11-27 16:45:41 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e608b63102382fa854a38d37f79ab158 SHA-1: 18ec555b3ecddf4c7a79a2a827220cdb5fe61c2d SHA-256: bd85bbc8cbb7a381ecbafbfc0b2980b6fc8eedb049933c999aa3fbe9c5aa77b2
214 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating a malicious redirector link and a PDF link farm. The ML classifier also flagged the document with high confidence. The primary attack pattern involves directing users to potentially malicious external sites, likely for phishing or to serve further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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
  • 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://traffmen.ru/strik?utm_term=ucsd+spring+break+study+abroad
    • https://gizarokidobibaw.weebly.com/uploads/1/3/4/3/134363860/biforiwop-maxopow-satat.pdf
    • https://zojopufowe.weebly.com/uploads/1/3/4/5/134523349/pexadavuguduv.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/36872e79-f545-4590-b568-098307ecc499/70359418606.pdf
    • https://uploads.strikinglycdn.com/files/c7b4b374-3aa6-404d-9991-c4f6480d15bc/solucionario_matematicas_4_eso_bruo_opcion_b.pdf
    • https://uploads.strikinglycdn.com/files/43f8cfee-18fc-4cd4-8e73-9c469b3af979/limbaugh_funeral_home_portland_tx.pdf
    • https://s3.amazonaws.com/jowutoneranemuk/bojemawakesugefadukaxuguw.pdf
    • https://uploads.strikinglycdn.com/files/271b0a66-9966-4fce-b3ca-4e7d10d9f895/low_carb_mediterranean_diet_food_list.pdf
    • https://s3.amazonaws.com/sizadagazagaj/78023635362.pdf
    • https://s3.amazonaws.com/muxegeza/dutch_colonial_home_colors.pdf
    • https://s3.amazonaws.com/selivuvumepaveb/billboard_music_awards_performers_2018_list.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_off0000c8c7.bin
d81c2aee2b95c24c43eaff32cdbc8e83d2b6380daa3882b45561bb0151b430fb
pdf-font-stream PDF embedded font (sfnt) at offset 0xC8C7 5508 bytes
font_01_sfnt_off0000db93.bin
d8fa5e8918f5ed8305c2b136a1d859eaa8730a7b8fc2da18d54beea263aeb575
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB93 10404 bytes