Malicious PDF — malware analysis report

Static analysis result for SHA-256 4205bffe56a81afb…

MALICIOUS

PDF

70.2 KB Created: 2021-09-04 03:50:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 1f2d32494c22097c917396bcdcf93a8b SHA-1: 90a6528c8ec11b78fd15645c746a52ff228cd969 SHA-256: 4205bffe56a81afbd18d40482e8d5d8ddc627e3c0db8807674f6e36a12979393
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, and contains embedded JavaScript. It also functions as a link farm, directing users to multiple external URLs hosted on potentially compromised or disposable domains, which is a common tactic for phishing or malware distribution. The presence of embedded JavaScript suggests an attempt to execute malicious code within the PDF viewer.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://sparan-art.ru/ckfinder/userfiles/files/43952267698.pdf In PDF document text
    • http://bestbuyfromindia.com/userfiles/file/memejugom.pdfIn PDF document text
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/adb494f918c74c16a7a3339aa8ca66a8/movubexabi.pdfIn PDF document text
    • http://slsnn.ru/content/files/liperuva.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16079cd3d5dfc5---makudipipale.pdfIn PDF document text
    • http://khaskhaan.mn/uploads/userfiles/files/85698169505.pdfIn PDF document text
    • https://madame-tina.com/ckfinder/userfiles/files/zuzedavisudaxebumo.pdfIn PDF document text
    • http://koszyczarek.pl/userfiles/file/21129900604.pdfIn PDF document text
    • http://rideabikenews.com/user_img/files/79784028604.pdfIn PDF document text
    • https://romalasergroup.com/userfiles/files/nomirela.pdfIn PDF document text
    • http://nhs1966reunion.com/clients/1/1c/1ca8f1639ee69cd7806809ed3bcda9bb/File/79560337088.pdfIn PDF document text
    • http://honda-vo.com/upload/file/vovozesepuriwozono.pdfIn PDF document text
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/160c7143d9d959---fuletibuxuboxepujibimim.pdfIn PDF document text
    • https://harpethvalleyhealth.com/wp-content/plugins/super-forms/uploads/php/files/c99e269ccbf68201e9710ff6fcd687ad/fufupag.pdfIn PDF document text
    • http://morethancars.nl/uploads/edytor/file/nisifepeteniga.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/22259b3be0a4ff2bdf0750bde82e8453/24059178256.pdfIn PDF document text
    • http://hnspkjx.com/d/files/13041232554.pdfIn PDF document text
    • http://chinhlytailieuluutru.com/media/ftp/file/12956838824.pdfIn PDF document text
    • http://373113.linker.tw/files/tetaruzako.pdfIn PDF document text
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b2a636602d---47251914395.pdfIn PDF document text
    • http://airelimpio.mx/img/editor/file/rifaxiwadesidozuva.pdfIn PDF document text
    • http://bugaboo-buffalo.eu/UserFiles/File/42092435534.pdfIn PDF document text
    • http://nollve.com/img/editor/image/file/12101220076.pdfIn PDF document text
    • https://www.vek-bg.com/app/templates/js/ckfinder/userfiles/files/faraxekeguxakojotawi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=manual+dibujo+arquitectonico+pdfPDF 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_off0000b31d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB31D 15440 bytes
SHA-256: a07eb17ff9d9912040d0d251c04db450d59101a0840fe5521a64e0e771385a9b
font_01_sfnt_off0000da21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA21 10952 bytes
SHA-256: 78d98c12d9f91f661621d1c44670a4197ea8559178d725740176c7133567b0bf
font_02_sfnt_off0000f319.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF319 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1