Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d73850b408dd06a…

MALICIOUS

PDF

75.7 KB Created: 2021-03-14 17:56:00 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 4de8455b43cb7715a6345e68f10240c3 SHA-1: 308848083db5142ed8ee8d2f7b170ef6c1ba701e SHA-256: 3d73850b408dd06a90a36393360ea538fbe0eff08211233cbbc6dc57d308e6a2
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, indicative of a link farm designed to distribute traffic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The embedded links and the nature of the PDF structure point towards an attempt to direct users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://nipisod.ru/wix?keyword=jack+of+spades+quick+guide PDF link annotation
    • https://cdn.sqhk.co/wavivatus/cgeHicv/satepav.pdfIn PDF document text
    • https://cdn.sqhk.co/sixojifez/jeqgiih/read_marvel_comics_online_free_no_download.pdfIn PDF document text
    • https://cdn.sqhk.co/sisowufabo/oRgiCCF/hockey_goalie_fight_gif.pdfIn PDF document text
    • https://cdn.sqhk.co/zoluxoni/geFhgyk/first_three_steps_for_treating_burns_and_scalds.pdfIn PDF document text
    • https://cdn.sqhk.co/baxoladipezu/9wigMS7/45401155168.pdfIn PDF document text
    • https://cdn.sqhk.co/kowaziwaso/3cNGEia/gowarinimaxedinoti.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379848/normal_60353dfe81601.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4460723/normal_5fc991a234853.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4445729/normal_6031f4d851b51.pdfIn PDF document text
    • https://cdn.sqhk.co/saguregifu/hchbhbz/balanced_scorecard_approach_to_performance_measurement.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4491410/normal_6033726cc19aa.pdfIn PDF document text
    • http://lolebunefa.iblogger.org/all_my_sons_act_2.pdfIn PDF document text
    • https://cdn.sqhk.co/kubepugemaki/ie5jljd/kodiak_gun_safe_atwoods.pdfIn PDF document text
    • https://cdn.sqhk.co/tavevalurov/qhbiipl/hidden_escape_lost_temple_walkthrough_chapter_7.pdfIn PDF document text
    • https://cdn.sqhk.co/gigemuji/bjakhhk/begexevadet.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367277/normal_5ff2d6aec5bdc.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://xidomuxi.rf.gd/27675946496.pdfIn PDF document text
    • http://dodinakek.rf.gd/folipasuxulituxigogupin.pdfIn PDF document text
    • http://wagadepepixapu.epizy.com/cookie_clicker_cheats_android.pdfIn PDF document text
    • https://5a1138df-423b-4a5d-a7c7-36223740754e.filesusr.com/ugd/a72fa8_3238b2e22f174711a36e42e2c3036047.pdf?index=trueIn PDF document text
    • https://29159626-56e2-4eb2-a8c1-eb081f451e44.filesusr.com/ugd/a58502_a024b443c3e64c34bb7b99b082158dfd.pdf?index=trueIn PDF document text
    • https://a39ac558-8fe8-437d-9e10-dc9402d6cb9c.filesusr.com/ugd/1ebe14_459fda3868fa448c9ec996a8b18abfcc.pdf?index=trueIn 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_off0000e93f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE93F 5372 bytes
SHA-256: 4006c2d9ee4a9d3e243a337c6bcfdef77d77a6389d6029f15acd15c944213c99
font_01_sfnt_off0000fb9e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB9E 11152 bytes
SHA-256: 0cca803de35b99e4899bccc063bef127abf7c048deecccf655555ec643eff138