Malicious PDF — malware analysis report

Static analysis result for SHA-256 4a066ff891b0d667…

MALICIOUS

PDF

70.3 KB Created: 2020-12-23 15:06:36 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-15
MD5: 8b4a89438bfae4ac0329c5b8fc746643 SHA-1: 14509f21a95ef4f2a68760deb585fff68d1db4c3 SHA-256: 4a066ff891b0d667e087566a9203e652d1442e47ec44903c5a88c677d00d967b
186 Risk Score

Malware Insights

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

The PDF contains numerous external links, identified as a link farm, with one prominent URL pointing to 'trafffe.ru'. Heuristics indicate this is a malicious PDF, likely a phishing or SEO spam document designed to drive traffic to potentially malicious sites. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://trafffe.ru/aws?utm_term=aprendizajes+clave+pdf+primaria+tercer+grado PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4403129/normal_5f9bd292c0df2.pdfIn PDF document text
    • https://sopakefexije.weebly.com/uploads/1/3/4/3/134398413/f76416c081.pdfIn PDF document text
    • https://lavofimezifo.weebly.com/uploads/1/3/4/3/134341346/77097bad6f17c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4389792/normal_5fa245744eb4a.pdfIn PDF document text
    • https://pagimoroxu.weebly.com/uploads/1/3/4/2/134265496/lufibomapimagex_ramaritijezagaz_simasubole.pdfIn PDF document text
    • https://lagukekejase.weebly.com/uploads/1/3/0/8/130815031/bibulasejoxuwo.pdfIn PDF document text
    • https://naxedomabaxa.weebly.com/uploads/1/3/1/6/131606472/kusaxudatowada.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/wexoteluwag/jinafepabelajedikerosojes.pdfIn PDF document text
    • https://s3.amazonaws.com/xilasisefi/acls_protocol_2019.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7f0085e0-d4df-41a6-9e0a-4bb60837f9bc/battlefleet_gothic_armada_achievement_guide.pdfIn PDF document text
    • https://s3.amazonaws.com/wusigipufuvowix/hospitality_industry_word_search_answers.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/95a4add3-4cfe-4538-a03d-0c876de35eaa/ddtank_pirata_2019_com_painel.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/755a6804-bdfc-4b14-aa24-7862f2c5bf6b/let_your_life_speak.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/bd955900-3f79-4b19-a099-f64a6194fd6c/sigubixuwepoguxepo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b1cfcaa5-6cc4-4525-9540-e21a5dc6fc0a/tuwul.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74d1c3e9-e72e-4311-8190-5c4605206b9c/lenovo_thinkcentre_graphics_card_upgrade.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6258cd5f-a310-403d-a468-a67492685b5a/recorded_cam_shows_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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b957.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB957 6744 bytes
SHA-256: b29f9350a720d2da9dc50567d08c4a82684db1fcb28a47e3a5788345b392d808
font_01_sfnt_off0000ca3c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA3C 5648 bytes
SHA-256: 8c9d2fcd5838639679894d5e1c46ab1f0e2ad30b49d543f730096ee18a9490dd
font_02_sfnt_off0000dd6f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6F 2268 bytes
SHA-256: 72a3fe65f0a21df30f240897224061cfa351088b80a4eb601fb5defb198ec993
font_03_sfnt_off0000e781.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE781 10388 bytes
SHA-256: 5f4bce23a17e4ac43494e15087ec7d979cac5ef6ec5881afa728063e9f4433bc