Malicious PDF — malware analysis report

Static analysis result for SHA-256 51c2ef48fb865664…

MALICIOUS

PDF

80.9 KB Created: 2021-09-13 13:30:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 745e243e5b04cb15fa8352482df050ad SHA-1: b2409efd9d77825b5f5d1dd48f66c2a11f2d2507 SHA-256: 51c2ef48fb865664aea2804fa116ee5129b0d514537cbdbbcb608027fcbe5d4f
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO abuse. While no scripts were directly extracted, the PDF structure and URL patterns suggest an attempt to redirect users to malicious or deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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
  • 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 http://csc0898.com/userfiles/file/20210912161510_lmbems.pdf In PDF document text
    • http://avision-italia.com/userfiles/files/69452346849.pdfIn PDF document text
    • https://alwillislifecenter.org/ckfinder/userfiles/files/83080961130.pdfIn PDF document text
    • http://maryalo.com/userData/board/file/senerulerejapuribomaruf.pdfIn PDF document text
    • http://telecycling.info/files/file/tofapeboxipaximibekeluguj.pdfIn PDF document text
    • http://tdsns.ru/userfiles/file/resubibeno.pdfIn PDF document text
    • http://bekescsaba.varosom.hu/userfiles/files/23047907765.pdfIn PDF document text
    • https://ncsccalgary.com/userfiles/files/47553563457.pdfIn PDF document text
    • https://pre-www.bridge-academy.com/uploaded/ckeditor/files/67110530129.pdfIn PDF document text
    • http://zhuoxinlaw.com/userfiles/file/20210909052747_186931248.pdfIn PDF document text
    • https://xn--72ca1bzcdf9cg5df4n5a8cei.com/userfiles/files/kuzikiwozubolebusuv.pdfIn PDF document text
    • http://ceomit.com/fckupload/file/dulofekumukipepibupek.pdfIn PDF document text
    • http://gtlmarinefuel.com/userfiles/file/38105527297.pdfIn PDF document text
    • https://kga-am-adlergestell-ev.de/kga/ckfinder/userfiles/files/tixifarimubamimali.pdfIn PDF document text
    • https://istanajp.net/contents/files/rixopimuxanefiwewudi.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/bezanodalujegodatugiriw.pdfIn PDF document text
    • https://ovistar-dz.com/ckfinder/userfiles/files/sazesarasoxobotuw.pdfIn PDF document text
    • http://maasmartcity.com/userfiles/file/nojefateboxewajedabudeta.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/geniburexi.pdfIn PDF document text
    • http://studiogaleazzo.eu/userfiles/files/96836568996.pdfIn PDF document text
    • http://oxigensupplies.com/shipinc/userfiles/files/8868928792.pdfIn PDF document text
    • http://legalinet.eu/userfiles/files/wonedadubonasowidovero.pdfIn PDF document text
    • http://eau-msu.ru/ckfinder/userfiles/files/74977162978.pdfIn PDF document text
    • http://jayeonrak.com/upfile_editor/2021/files/89729903696.pdfIn PDF document text
    • http://www.nandomoraes.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16134f8e3a998a---38185844118.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=transformers+robotsindisguise+mod+apkPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d5ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5AB 17824 bytes
SHA-256: 42402325259cd0983a817749fed9248c82f1313d84fd198b3b59a01dbdde7e37
font_01_sfnt_off0001046f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1046F 11088 bytes
SHA-256: 9b4d136f5280f7b224d6b2d7ed1d11aef937298f609e9635defdf38c201c0182
font_02_sfnt_off00011de5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1