Malicious PDF — malware analysis report

Static analysis result for SHA-256 dba9c832ab8b2781…

MALICIOUS

PDF

69.9 KB Created: 2021-09-27 01:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 88edb418e617fa9fb12344288973b085 SHA-1: 9f542e6634b970b2b40ffe8e3edd721d7a40e6b7 SHA-256: dba9c832ab8b27818b42f26fbad02a588a6ce8dfef7e481ad96c1999528e418f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Analysis reveals it functions as a link farm, containing numerous URLs pointing to compromised WordPress uploads and disposable hosting domains. This suggests an attempt to redirect users to malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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
  • 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://interstudy.net/userfiles/file/labebamavuza.pdf In PDF document text
    • http://abwingsva.com/uploads/files/75212535695.pdfIn PDF document text
    • http://ownlines.com/upfiles/file/44961137189.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a2ffbe1ce---zepevixomukevasi.pdfIn PDF document text
    • https://www.baileysmilk.com/wp-content/plugins/super-forms/uploads/php/files/aff3dcbc2ae3be8ac91190e8da78fa5d/dopepazonajutar.pdfIn PDF document text
    • http://touristclub.in/userfiles/file/xikajefusidagawiguwir.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161423284986c8---bawokijetod.pdfIn PDF document text
    • http://sistarelaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fezupugifu.pdfIn PDF document text
    • http://grupophi.es/uploads/files/vabazatomot.pdfIn PDF document text
    • https://matratva.in/userfiles/file/vidixedewitebune.pdfIn PDF document text
    • https://mikepromedia.com/wp-content/plugins/super-forms/uploads/php/files/08238db547ce31dc1502645de906d23f/susetopimavoxu.pdfIn PDF document text
    • http://4darchitecture.org/img/all/pisonarimapidekudasegiv.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/gevud.pdfIn PDF document text
    • https://mobile-translator.eu/app/webroot/media/files/fifowuxefemaritonife.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/27648633575.pdfIn PDF document text
    • http://giayviettri.com/img-ftec/files/mevosafapawiza.pdfIn PDF document text
    • https://sfeerweter.nl/userfiles/files/32636343746.pdfIn PDF document text
    • http://dogalakustik.com/depo/sayfaresim/file/70995466942.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/161484dd931afe---73524454409.pdfIn PDF document text
    • https://maftplayer.net/calisma2/files/uploads/88552216665.pdfIn PDF document text
    • http://domplus.su/userfiles/files/85306228169.pdfIn PDF document text
    • http://hftyby.com/upload_fck/file/2021-9-8/20210908000359448830.pdfIn PDF document text
    • http://www.aragonemprendedor.com/userfiles/files/durimikuzilowawivaje.pdfIn PDF document text
    • http://blekinge.boj.se/uploads/userfiles/files/72508170854.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=best+screencast+app+for+androidPDF 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_off0000b33f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB33F 10620 bytes
SHA-256: 27527d5fb8466c1b9b0efbecb104a536e46ec4a6c15353cf2a085fb76265861a
font_01_sfnt_off0000cba6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBA6 15308 bytes
SHA-256: 1aa7e5f4864bd30d59fc14b337341e3515cc7ece5b02bdbda19446e449a3a4f7
font_02_sfnt_off0000f19c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF19C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1