Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3c166f1c3df8788…

MALICIOUS

PDF

89.6 KB Created: 2021-03-27 18:08:02 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-10
MD5: b5f395dd2e097a58e4f5038e3832c00b SHA-1: 515cc8380ba0d5a4325c274a21d0e6d90979fc14 SHA-256: a3c166f1c3df878815ff3fa66d4e3c4761a853ef88fec483bd94b6376e3137e5
184 Risk Score

Malware Insights

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

The PDF contains multiple embedded URLs, with one critical heuristic firing indicating it links to known malicious redirector infrastructure. The ML classifier also strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of numerous links and the critical redirector alert suggest the document's primary purpose is to lure users to malicious sites, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 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.
  • 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://yafferge.ru/award?keyword=catalase+test+pdf In PDF document text
    • https://cdn.sqhk.co/kuzetuzame/fgchcia/63833031343.pdfIn PDF document text
    • http://gadetebes.sportsontheweb.net/74991535503.pdfIn PDF document text
    • http://bunedose.22web.org/aukey_dual_dash_cam_manual.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4383460/normal_5ff5b7f78a6f8.pdfIn PDF document text
    • https://cdn.sqhk.co/mugegiduveb/3hfBZhd/78683933236.pdfIn PDF document text
    • https://cdn.sqhk.co/tinipuded/vhfghje/mopakimotedi.pdfIn PDF document text
    • https://cdn.sqhk.co/motuvitewodi/BhcjaGD/moser.pdfIn PDF document text
    • https://cdn.sqhk.co/kelopifagisu/emOrihj/shark_attack_videos.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393489/normal_603d05372536e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4414173/normal_604437daa7855.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://rijemow.onlinewebshop.net/wajalulezafakuri.pdfIn PDF document text
    • https://s3.amazonaws.com/wazorixekunafob/gediw.pdfIn PDF document text
    • https://s3.amazonaws.com/geraromu/37273439177.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb1efca9-46b6-49d4-b66d-2868e0a9657a/jufemakagoruvoboz.pdfIn PDF document text
    • http://lufogadiza.rf.gd/voxedifemegibabezejol.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/92347d90-530c-4194-b348-6cae66447fa5/13757355920.pdfIn PDF document text
    • http://verekoxamokit.epizy.com/gotevosupevenanebibixut.pdfIn PDF document text
    • http://repoxulatuju.rf.gd/lisokodugofazorerenuduzi.pdfIn PDF document text
    • https://s3.amazonaws.com/lupebesu/effingham_performance_center_seating_capacity.pdfIn PDF document text
    • http://jabodegodonirad.atwebpages.com/1203677133.pdfIn PDF document text
    • https://s3.amazonaws.com/lolijexejomak/kerbal_space_program_control_surfaces_inverted.pdfIn PDF document text
    • http://baxosadukosi.rf.gd/91605414175.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eb7e567a-6c3e-42e6-8f13-813edd1417c9/41195214506.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/348cd9b6-e5c5-4086-9359-e7bf4f277cd5/barrons_essential_words_for_the_toefl.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_off0001209b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1209B 4844 bytes
SHA-256: 25afbca274d06bb117ac6150badcc2eb55d596b4e431be296d9447c9806f59eb
font_01_sfnt_off0001312a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1312A 12716 bytes
SHA-256: 0d947fe660f80b0a500e9a649c5e79adbbaf288bbdbf6f25c64995fcecfff136