Malicious PDF — malware analysis report

Static analysis result for SHA-256 16830d500ad35830…

MALICIOUS

PDF

89.7 KB Created: 2021-08-06 19:53:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: c93a00950d026b2bf86580fdbf9bbca9 SHA-1: d96ef6f15119c967fb3ea2366d0e1b652b245444 SHA-256: 16830d500ad3583025c37b98722f1f00480b7c0743b038e4080518e160a56a39
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external URIs and link farm heuristics, indicating a likely attempt to redirect users to malicious websites. The ClamAV detection and ML classifier strongly suggest this PDF is malicious, specifically flagged as phishing and a trojan. While no scripts were explicitly extracted, the PDF structure and embedded URLs point towards a phishing or malware distribution campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://krisoc.ru/uplcv?utm_term=curso+de+adestramento+de+c%C3%A3es+pdf PDF link annotation
    • http://oneself.pro/wp-content/plugins/formcraft/file-upload/server/content/files/160aa833b5a24d---53868240209.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/79da2b1f02492faac550f107b44b8b10/91789885229.pdfIn PDF document text
    • http://kiapelhrimov.cz/UserFiles/File/79352769877.pdfIn PDF document text
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/e9666e3478d87342c3a90c08882050c3/milejowovisaz.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca65cbb221---sarojigelulomakazibofiko.pdfIn PDF document text
    • https://ecoinkworld.com/wp-content/plugins/super-forms/uploads/php/files/04c567c47365ae347b0ac5801830451d/7706992504.pdfIn PDF document text
    • https://pluckywize.com/wp-content/plugins/formcraft/file-upload/server/content/files/16106e8c7a8a42---xajajanamajuse.pdfIn PDF document text
    • https://avphunter.ro/ckfinder/userfiles/files/ruzevonef.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e134cc679f---399381576.pdfIn PDF document text
    • http://cga82.com/admin/File/42936501774.pdfIn PDF document text
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16098bf2629435---92456239010.pdfIn PDF document text
    • https://spencershaulageltd.co.uk/wp-content/plugins/super-forms/uploads/php/files/0d1d9a222b4dc7a61d98601fe1eb5d93/gajiduluninebunoku.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/48992709151.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/u1kpargjhprusr1nnfs7c2r7j1/67995750229.pdfIn PDF document text
    • https://amblamy.ee/upload/file/84415955243.pdfIn PDF document text
    • http://babyindex.nl/images/uploads/wofaludejirikoritanuzerot.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/7194d7ebcc161d312fe2b0b6a7211532/lewubasiburevivorimosiva.pdfIn PDF document text
    • http://straub-online.ch/userfiles/files/47853602771.pdfIn PDF document text
    • http://fonnepal.org/userfiles/file/43737615891.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c858d27227d---58590614533.pdfIn PDF document text
    • https://dongytueduc.com/wp-content/plugins/super-forms/uploads/php/files/6hupofd0asvvja0a1i5f61g1nh/megotewigavefigokexoxoba.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/20825772366.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608183d9073e8---fiwop.pdfIn PDF document text
    • http://krindustria.com.br/site/wp-content/plugins/formcraft/file-upload/server/content/files/1606f547875783---35022131813.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_off0000f495.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF495 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010cac.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CAC 11040 bytes
SHA-256: 820002348acaa027a7fe1a888e33968a61fe26d87ccea969548c2539369a5737
font_02_sfnt_off000125f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125F9 19932 bytes
SHA-256: eeab30fb753fddb0364c19234b194d8a2d41fcfa05abe86655a1597c2e67fe0a