Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8f21339d4b2ee38…

MALICIOUS

PDF

86.2 KB Created: 2021-09-18 04:25:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 7c9758487321e6851fba414e0d0f5089 SHA-1: 318b2c31db75b35554d5dfd96cfbbb4a4370ec78 SHA-256: c8f21339d4b2ee386b09b8d149874d4cad130324e57de1fb921e58f59b07e4e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically identified as a phishing or trojan. It contains numerous embedded URLs that function as a link farm, directing users to various domains, some of which are hosted on compromised CMS upload storage. The presence of 'utm_term' parameters in some URLs suggests an attempt to track user engagement with potentially deceptive content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://crewmak.ru/uplcv?utm_term=the+graveyard+book+graphic+novel+pdf PDF link annotation
    • http://sampoernastrategic.com/uploads/image/files/58734840712.pdfIn PDF document text
    • https://casasholidays.com/scgtest/team-explore/uploads/files/3190429504.pdfIn PDF document text
    • https://mmagame.com/userfiles/file/34835376852.pdfIn PDF document text
    • http://lynxauto.ru/userfiles/file/vesaretomevavebafoziw.pdfIn PDF document text
    • http://as-eng.biz/userfiles/file/fazod.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/161452b7de053e---37167597540.pdfIn PDF document text
    • http://coimbrasoftware.hu/images/uploads/files/tekidipadilero.pdfIn PDF document text
    • https://movimientofamiliadejesus.com/images/uploaded/file/70379044860.pdfIn PDF document text
    • https://makanbanyak.net/contents/files/12878384728.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/43441025746.pdfIn PDF document text
    • http://clinicaveterinariacene.com/userfiles/files/wupaliwutejogenuzogenuxe.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613aed09d1ad5---12035744469.pdfIn PDF document text
    • http://www.jfac.kr/ckfinder/userfiles/files/vamegotojoge.pdfIn PDF document text
    • http://alpinedelhi.com/userfiles/files/fagugawujid.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/64408960979.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/1614531b67ed3d---gigofogujojoxez.pdfIn PDF document text
    • http://ozdermusavirlik.net/userfiles/file/29987026332.pdfIn PDF document text
    • http://euromarkcreations.com/new/fck_img/file/21176273680.pdfIn PDF document text
    • http://gotween.com/userfiles/file///bojumuxowuloponokikazuvof.pdfIn PDF document text
    • http://ediliziaunoaventi.com/userfiles/files/fabaraw.pdfIn PDF document text
    • http://clairerolo.com/userfiles/file/30971427798.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/pogijuziwetejalosevure.pdfIn PDF document text
    • http://gurukripapublicschool.org/userfiles/file/25502767192.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139ee219ea09---1108852561.pdfIn PDF document text
    • http://skyrybupaslaugos.lt/uploads/files/lanokesetuxuwuxax.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/49824579516.pdfIn PDF document text
    • https://omegaplus.bg/uploads/pages/files/80481763977.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
    • 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_off0000ed1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED1F 17300 bytes
SHA-256: d937758594fe4584ca97147018eccb3391b02ac63622841e9f84596da38d45cf
font_01_sfnt_off000119b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119B0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000131c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x131C7 11008 bytes
SHA-256: 382d88a21425933b9d9f8355daae9212f7d326eee5c0372a403e9174d29dcd8e