Malicious PDF — malware analysis report

Static analysis result for SHA-256 631848e31e9d34e2…

MALICIOUS

PDF

97.3 KB Created: 2021-03-10 20:13:10 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-22
MD5: 81a22dacacd449005997bdee21aa3b24 SHA-1: fd65b5fc88cae0b92391f5696f462bfd517ef7bc SHA-256: 631848e31e9d34e2cac6718dd06593737057f2a99db8f7d3a240564a2329e0d6
134 Risk Score

Malware Insights

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

The PDF contains a deceptive link disguised as a download for 'Advanced trainer 2020 pdf download'. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates the PDF is part of a link farm on disposable hosting, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to deliver a payload via the embedded URL.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://fokemale.ru/award?keyword=advanced+trainer+2020+pdf+download PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4367912/normal_5fcebecd003ba.pdfIn PDF document text
    • http://tipofeliluget.medianewsonline.com/88778976197.pdfIn PDF document text
    • https://sivajusirev.weebly.com/uploads/1/3/0/8/130814673/gixofeti.pdfIn PDF document text
    • https://soxigirotum.weebly.com/uploads/1/3/0/9/130969819/b9e725594.pdfIn PDF document text
    • https://sobexezawatu.weebly.com/uploads/1/3/4/9/134903145/nepavaneboro_miriza.pdfIn PDF document text
    • https://guwizufim.weebly.com/uploads/1/3/0/8/130813931/4f7ed12d.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4461780/normal_601aab80d1eb5.pdfIn PDF document text
    • https://pujatimosu.weebly.com/uploads/1/3/2/6/132681823/paxotejesi.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4496148/normal_600905f908c54.pdfIn PDF document text
    • http://wujejejifi.mygamesonline.org/denon_avr_x2000_receiver.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/39b4e5d7-519b-469b-8515-94f7d481a0ed/wigiginomanovasuti.pdfIn PDF document text
    • http://dezabefuzureb.rf.gd/m_audio_keystation_49es_review.pdfIn PDF document text
    • http://giwofigu.epizy.com/63829199597.pdfIn PDF document text
    • http://valapapiwusujeg.rf.gd/61500996615.pdfIn PDF document text
    • http://xologikaju.atwebpages.com/tudoxut.pdfIn PDF document text
    • http://jumebesatupa.epizy.com/zojeraxagenuvujudagukim.pdfIn PDF document text
    • https://b3d988c2-7a7d-4c3c-9141-221b6550481e.filesusr.com/ugd/9dda13_b000136293b9447487d352f3ba4e56d7.pdf?index=trueIn PDF document text
    • http://gaxenomepelir.epizy.com/giratas.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ddc3eb10-d9d5-4f58-8f20-7c7f5324af66/maxikigemaponedel.pdfIn PDF document text
    • https://72b50e20-f79f-40ca-96b4-24bef83e308f.filesusr.com/ugd/1a1092_b728830a382d45daa85e1218e001b3fe.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
    • 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000123cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x123CF 6744 bytes
SHA-256: b29f9350a720d2da9dc50567d08c4a82684db1fcb28a47e3a5788345b392d808
font_01_sfnt_off000134b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134B4 5384 bytes
SHA-256: 08b814c619145cfe0a3dbe5dfc2e5f0f1c31a1c301963660bfc0d7436de19e92
font_02_sfnt_off0001472a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1472A 16164 bytes
SHA-256: d806b1b7d1afa5322f7d24278c8973022858d08aa9f68174d46a20afa964c35e