Malicious PDF — malware analysis report

Static analysis result for SHA-256 98f619fcc65258a1…

MALICIOUS

PDF

69.2 KB Created: 2021-09-26 03:56:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 3262b0cc5e0939dab6bdd92e4990847b SHA-1: 2a9378918b6c000585d02bafb2bad058a92f61b7 SHA-256: 98f619fcc65258a18e676100a915f9b47ded2041715bb769fa0872cfbe16bf0a
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it contains a link farm pointing to compromised WordPress upload storage and disposable hosting, suggesting a phishing or malware distribution lure. The PDF structure itself is also noted as having duplicate object bodies, which can be used to obfuscate malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136b7987dd8e---8360073211.pdf In PDF document text
    • https://ntiverification.com/userfiles/file/dujetimeruxavukowomatonem.pdfIn PDF document text
    • https://www.cylinder96.ru/admin/ckfinder/userfiles/files/33153643379.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/tezijuvunoxe.pdfIn PDF document text
    • https://xn--interpeas-r6a.es/upload/files/feneto.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/viwaz.pdfIn PDF document text
    • https://onhimalayas.com/ckfinder/userfiles/files/doxudagiximiwonalewafi.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/xenufosodiwolodamig.pdfIn PDF document text
    • https://hiroyoung.com/data/files/vevivizakoton.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/9cuhfo2snq70uf4nnc1slpdgr8/lewuno.pdfIn PDF document text
    • https://toocapen.com/files/42444093770.pdfIn PDF document text
    • http://pmrs.ps/userfiles/file/xutegelebekewigobezoj.pdfIn PDF document text
    • http://mawratanews.com/armedia/uploads/files/37814281611.pdfIn PDF document text
    • http://studio-castiglioni.com/userfiles/files/kisagakozaxovinapidovud.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/67460888296.pdfIn PDF document text
    • https://rallstarawards.us/nbloom/fckuploads/file/10890242594.pdfIn PDF document text
    • http://atel-j.nl/uploads/files/91282852633.pdfIn PDF document text
    • http://canissapiens.com/images/uploads/file/kinitajifo.pdfIn PDF document text
    • https://charterfori.ir/basefile/charterforiir/files/nokopanoxivirunubefab.pdfIn PDF document text
    • http://sicilyontable.it/userfiles/files/zudew.pdfIn PDF document text
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614c6ff504c46---24058950861.pdfIn PDF document text
    • http://naturalfurnish.com/userfiles/file/69680291428.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=craftsman+apk+descargarPDF 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_off0000b063.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB063 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000c87a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC87A 10828 bytes
SHA-256: 604e1a4ee63bd5b428afc8153981ae32869486b039258bdce1c2b6cf1cda28c0
font_02_sfnt_off0000e144.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE144 15108 bytes
SHA-256: ad0885017e0af6436974cb052527326076fbacec3848a00c64855f5208a99f6d