Malicious PDF — malware analysis report

Static analysis result for SHA-256 c8c41f8d1bf8a65a…

MALICIOUS

PDF

81.1 KB Created: 2021-09-17 07:35:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: dc2d58e7cf78ea3c4e8882edb8b44adb SHA-1: 5e620fa3db94a9e0914ac7ad3974140a64aa02a4 SHA-256: c8c41f8d1bf8a65aafb293dcbe49f636172205b6ec6185753663dee01836a3b0
156 Risk Score

Malware Insights

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

The PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The presence of these links and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest a phishing or malicious redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 http://harasim.cz/uploaded/files/43293197059.pdf In PDF document text
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136ce73e46e5---foleka.pdfIn PDF document text
    • http://lecostationery.com/files/file/71774429216.pdfIn PDF document text
    • http://xn--80aer5aza.xn--19-kmcm3c.xn--p1ai/ckfinder/userfiles/files/95724898562.pdfIn PDF document text
    • http://viermaalh.nl/Bottesteyn/Site/afbeeldingen/file/kexakavajobinagapo.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210913130817.pdfIn PDF document text
    • http://rockbond-aac.com/id-admin/fckImages/file/tizenusajevupe.pdfIn PDF document text
    • http://kiko168.com/UploadFile/file/20210907094908946.pdfIn PDF document text
    • http://metamorfozyayincilik.com/userfiles/file/88085919385.pdfIn PDF document text
    • http://alpinist.store/sribati/editor/uploadfiles/degojenapowibaduwotope.pdfIn PDF document text
    • http://studiosantomauro.it/userfiles/files/37370874040.pdfIn PDF document text
    • https://npkfertilizerproduction.com/d/files/tuwilotapasitukujowodisif.pdfIn PDF document text
    • http://pappteam.hu/userfiles/file/78716532250.pdfIn PDF document text
    • http://daltan.hu/userfiles/file/94096420222.pdfIn PDF document text
    • https://joyfool.art/wp-content/plugins/super-forms/uploads/php/files/4acc47084e9932911e8182ae5a852d85/mumegon.pdfIn PDF document text
    • https://samavetpharm.com/userfiles/files/95290394405.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/ragimifefuwave.pdfIn PDF document text
    • http://tienhasteel.com/app/webroot/upload/files/64566201540.pdfIn PDF document text
    • https://hum639hb2-hh38.com/contents/files/65314098268.pdfIn PDF document text
    • https://superchills.com/userfiles/file/vububovefalodiwajitozopo.pdfIn PDF document text
    • https://sandalyecenneti.com/wp-content/plugins/super-forms/uploads/php/files/7n796g9n5866hmpjrbbkas7fv4/37589674523.pdfIn PDF document text
    • https://giaphutelecom.com/tctt/sites/aaa/file/89554943011.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=the+mortal+instruments+graphic+novel+read+onlinePDF 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_off0000d820.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD820 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f032.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF032 17348 bytes
SHA-256: d65833bbdbcdec02a8c4bff573ca84728bcb58ed06f0e8e1993057e31bcea61e
font_02_sfnt_off00011ce7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11CE7 11092 bytes
SHA-256: e2343ba32e24e202b532d575837af22bee709d8200c0566d6d16483564c16265