Malicious PDF — malware analysis report

Static analysis result for SHA-256 28e610b75951af71…

MALICIOUS

PDF

104.9 KB Created: 2021-07-15 18:05:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 797c2e73baaa9a29761ad5f9849e28b0 SHA-1: afa89468691c8d46179b97acef1392ab8bbd2f48 SHA-256: 28e610b75951af71d2b04d1fa7be34af0cc1f3c6f6edc609501b059e16775262
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links to compromised WordPress sites and disposable hosting, suggesting a phishing or malware distribution campaign. The presence of embedded URLs and the nature of the heuristics indicate that the document is designed to redirect users to malicious external sites, likely to download further payloads or harvest credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9874

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
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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://coretry.ru/uplcv?utm_term=nts+computer+science+past+papers+pdf
    • https://empylean.com/wp-content/plugins/super-forms/uploads/php/files/iveskcq8qte9fko1p4pttpsm39/gevodamaraziziwuxalidumo.pdf
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608ed821557bb---70760106201.pdf
    • https://sharzh-ufa.ru/wp-content/plugins/super-forms/uploads/php/files/efa4b2d2677dec534a512c1dd84ed243/jatadivedurobuwoli.pdf
    • https://flyfinz.com/userfiles/files/rafidujevagagokesaladivew.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c30b84d9681---94041143734.pdf
    • http://malbreil.com/userfiles/file/38507604643.pdf
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd5ecefc42---subosusewanoxula.pdf
    • https://anzmrrn.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c173116d83e---jaxodejidikatiduwepikag.pdf
    • http://biirbeh.mn/images/content/file/fudamatexilupivi.pdf
    • https://luxmarketing.agency/wp-content/plugins/super-forms/uploads/php/files/l54uce6n3cu4t453a7008ttt8t/11401788379.pdf
    • https://workinhotel.com/upload/fckfile/35418879999.pdf
    • http://vdgairconditioning.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16081d07f703c5---gosobatakelinikokirato.pdf
    • https://clubforeducation.com/FCKeditor/userfiles/file/zikilivunom.pdf
    • https://kurtoglumob.com/upload/file/79030346845.pdf
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160c3a204ec41d---jazuwoziginoviluxatob.pdf
    • https://xuantruongtech.com/images/ckeditor/files/1349823026.pdf
    • http://ventilyatsia-v-sochi.ru/ckfinder/userfiles/files/rolewisitorinokiribegi.pdf
    • http://hi-reid-solutions.com/wp-content/plugins/super-forms/uploads/php/files/d614fc2735927d4407c339b85676ea57/92847860639.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/0b0ab084447a91f16682483a7cc692be/93733374398.pdf
    • http://www.sbawerribee.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c33f6e8b08c---24315521388.pdf
    • https://limblength-sldf.com/userfiles/file/tejijununegubo.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608ecb840b2b5---2910906372.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071af6be0aef---96242181043.pdf
    • https://bawaniint.com/ckfinder/userfiles/files/86525572545.pdf
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/o5m7kut2km78tbudc0ung6k850/duludepagoweput.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_002_off00010be1.bin
44f16369416f961558d0bd26916092ffb8319d0d48541ba6dcda1941f7d9d787
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x10BE1 24780 bytes
font_01_sfnt_off000137ce.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x137CE 16792 bytes
font_02_sfnt_off00014fe0.bin
c06e11340b6c3a5547a5fcc92d6f53ac8ab5c2f67f0eeaca03a073360832024a
pdf-font-stream PDF embedded font (sfnt) at offset 0x14FE0 17184 bytes
font_03_sfnt_off00017cc2.bin
7b30b17427a581172f7ec82c30df2d59cce3358c1dc92a466a30afa2f44efbb0
pdf-font-stream PDF embedded font (sfnt) at offset 0x17CC2 10812 bytes