Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d51ef9430c4d498…

MALICIOUS

PDF

69.4 KB Created: 2021-05-07 09:13:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: d64d18a8035706b2defb1cb072b77ca4 SHA-1: 3069bd0a428e49acb06e33c2b92fd9b68bb99b86 SHA-256: 6d51ef9430c4d4985c56f5004337a33d66e35338b45b39d97266d408db3d0039
206 Risk Score

Malware Insights

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

This PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of numerous external URIs and the overall structure point towards a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://pelibifir.ru/strik?utm_term=free+worksheets+on+synonyms+and+antonyms+for+grade+4 PDF link annotation
    • https://cdn.sqhk.co/dubikureta/4ij8ibg/bugs_bunny_no_meme_blank.pdfIn PDF document text
    • https://cdn.sqhk.co/viwiratoposu/3Kia1mP/funny_notification_ringtone.pdfIn PDF document text
    • https://cdn.sqhk.co/tuwagezo/duiejfB/lokadu.pdfIn PDF document text
    • https://cdn.sqhk.co/loberutebe/hf4njaC/5725112615.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4474470/normal_605b4e30ea9e7.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4457861/normal_6054f62928022.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4487665/normal_6019056fbc9cf.pdfIn PDF document text
    • https://cdn.sqhk.co/laruxibut/ieiihgc/human_fall_flat_new_levels_xbox_one.pdfIn PDF document text
    • https://cdn.sqhk.co/nazopekujavi/WqhgdcM/wolf_simulator_games_for_pc.pdfIn PDF document text
    • https://cdn.sqhk.co/fikalibumi/pQ3U4sG/manual_carestino_3_en_1.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://95e354e6-8561-4e52-807b-deb85f3b5fdd.filesusr.com/ugd/ca9b0a_3e38883360ec42198539d72f38b608f7.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/redegelesibif/how_to_be_a_good_cashier_at_walmart.pdfIn PDF document text
    • https://1138278f-e8d0-45ef-aef3-dbdd7428ac52.filesusr.com/ugd/5be868_a8be5cc31a4843ddab80fead93f8be2a.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc3c97f0-acf4-4517-83ef-106654e5d2f0/doxemetuturi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c7e1ffe-5cd4-49a2-9651-50089aada921/yanmar_injector_pump_rebuild.pdfIn PDF document text
    • https://bd04a250-715b-4db0-8087-55ec2f714cf5.filesusr.com/ugd/0c2191_4c77733a5e8e41c2aacd8656fe7c2356.pdf?index=trueIn PDF document text
    • https://a86a6b26-b473-4b55-b9aa-7628a2bff077.filesusr.com/ugd/4f270c_7f1330bf78254701abf5baca75b79465.pdf?index=trueIn PDF document text
    • https://377d1c6c-8747-407e-9a0d-bb8234813250.filesusr.com/ugd/f0b1fd_bcee0e6324b6484da2ddf2b521b0d16a.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/mujesogi/julian_calendar_2021_download.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_off0000d20a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD20A 5592 bytes
SHA-256: 3a6870a6c4ae906cdcd91d23afc35eb1ea09eb2b5b45249ad595266a5d26aa58
font_01_sfnt_off0000e50e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE50E 10252 bytes
SHA-256: fc0e7939f4505b377bf86b69b1b9e9e4c07dd64f46a96e30501b75b378140b31