Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb1c25d8b04389ae…

MALICIOUS

PDF

89.4 KB Created: 2021-07-23 02:47:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 7c59f0b8fd8eb9d6d72108f6ae5531ff SHA-1: 3c5ab951907918b33fd73d6a30192d5794f01b80 SHA-256: bb1c25d8b04389ae35466fd0a9ca8e565ec0596f0f6dc899605491272726214d
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier. Heuristics indicate it contains a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO poisoning attack. The document body is heavily obfuscated and appears to be malformed, likely due to the wkhtmltopdf authoring application.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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 http://ivepe-elearning.gr/assets/UserFiles/mainHome/file/nipunogizototenuwi.pdf In PDF document text
    • http://infunplastic.com/d/files/59557578218.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/vuwufufobitozilojuzowebu.pdfIn PDF document text
    • https://klubkanine.com/home/klub/public_html/ckfinder/userfiles/files/rifabejasudokukemiwido.pdfIn PDF document text
    • http://prestopc.it/upload/file/lulivifidoleraso.pdfIn PDF document text
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d9713966234---45474116614.pdfIn PDF document text
    • http://vipnjl.com/userfiles/files/sugolokofa.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160704d44d5090---39893517570.pdfIn PDF document text
    • https://sinarwaja.com/account/files/19955353370.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092800f8cf58---58215916041.pdfIn PDF document text
    • http://wbbray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9a6683337---mupus.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608063ef14b13---38462159734.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160830a50b806b---92411923807.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070252d85cf6---nepabitijukewegum.pdfIn PDF document text
    • http://memphiscentral1969.com/clients/865565/File/13742921934.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bd999f26088---resigas.pdfIn PDF document text
    • https://taxforce.nl/userfiles/files/katizirofodudumi.pdfIn PDF document text
    • https://evermoral.hk/upload/file/1626212775.pdfIn PDF document text
    • https://yuss.it/file/60964940067.pdfIn PDF document text
    • https://priscar.com/documents/files/46023832730.pdfIn PDF document text
    • http://www.iqubz.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef5a516277---kinologuwaxop.pdfIn PDF document text
    • https://www.freshstartdigitalmarketing.com/wp-content/plugins/super-forms/uploads/php/files/2c5a67be10731dde223929c306f6bd79/11217220075.pdfIn PDF document text
    • https://lawpropertyconsultants.co.uk/wp-content/plugins/super-forms/uploads/php/files/vtnv4di6puiocc88np7h631m79/matusaz.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/baxosokelobozudekisu.pdfIn PDF document text
    • https://tavio.ru/files/file/wepudanodojusi.pdfIn PDF document text
    • https://mfdesign.hu/files/file/fijedekolos.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075ccafea561---simikavirexosozifuwe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=empiricism+is+the+view+thatPDF 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_off0000fa26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA26 17804 bytes
SHA-256: c17c4816bfe0e8fa3c5a605c2ba876284d3abd09a9c8d79d77449d3d3f6f3b1f
font_01_sfnt_off00012779.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12779 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013f90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F90 10504 bytes
SHA-256: 920c4daa9e425076ab2d8fa699e4cbd7dafbc02a2ae4bcc851cd5f7b44469322