Malicious PDF — malware analysis report

Static analysis result for SHA-256 fc31aa3d8ac88aa9…

MALICIOUS

PDF

81.8 KB Created: 2021-09-04 01:15:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: e835125ff3b68fde472e0cb5c3fc8aa9 SHA-1: f2df411db11adad2187130069280437354d353e0 SHA-256: fc31aa3d8ac88aa920b0066641db254d7e87971d6f8880c08c66b7ca5ce828f8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged by multiple heuristics and a machine learning classifier as malicious, with ClamAV identifying it as a phishing trojan. The file functions as a link farm, containing numerous URLs that point to compromised websites and disposable hosting, likely intended to lure users into downloading further malware or engaging in phishing activities. The presence of external URIs and link farm characteristics strongly suggests a malicious intent to redirect users to harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9946

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://catamma.ru/uplcv?utm_term=danmachi+light+novel+volume+12+pdf+download PDF link annotation
    • http://fullcolorspandoeken.nl/userfiles/file/zesiserajeritum.pdfIn PDF document text
    • https://vidolamerica.org/wp-content/plugins/super-forms/uploads/php/files/2ba2baf2ac485f765e3ed59fa64148b3/nejogopasi.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/c8f3b966539e55ca7bbd03333df24c9f/84321630271.pdfIn PDF document text
    • http://chrislahoda.ca/userfiles/file/wixokepexajikagakipowe.pdfIn PDF document text
    • http://candleelectricals.com/uploaded_files/userfiles/files/pekenonagizizezo.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a06922d47---8404916092.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/abbcc5ef668589315bb3167d9b28d394/munivo.pdfIn PDF document text
    • http://bellezaeimagen.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/16076fafd98d4c---55010853734.pdfIn PDF document text
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d84399e73fb---dowavinivakugefulufis.pdfIn PDF document text
    • http://bburago.info/admin/fckeditor/userfiles/file/23157911571.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f267c58a631---tiwumaviforuliwijenobusuv.pdfIn PDF document text
    • https://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/jt46c21ijrmr8le1fa80qcoq5s/13509358385.pdfIn PDF document text
    • http://saga.diamonds/uploads/ckfinder/files/98850594644.pdfIn PDF document text
    • http://richmediahouse.com/admin/uploads/file/fagawiteza.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b14ab16d170---53164738080.pdfIn PDF document text
    • http://astro2sphere.com/admin/images/file/binisetufumajuramuv.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607668cfecfdd---wejine.pdfIn PDF document text
    • https://oxfordjsr.com/userfiles/file/tuxumogolutuzizi.pdfIn PDF document text
    • http://campfirewtx.org/userfiles/file/xagorojufovazudur.pdfIn PDF document text
    • http://kondicionery-ivanteevka.ru/upload_picture/file/danoro.pdfIn PDF document text
    • http://1careglobal.com/upload/files/32775137807.pdfIn PDF document text
    • https://snabavto.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2ec1ea7328---zojasidopiviretexeli.pdfIn PDF document text
    • https://www.grandeprairie.org/wp-content/plugins/formcraft/file-upload/server/content/files/160d21fa0c24b7---wakidezuwevamawiriju.pdfIn PDF document text
    • https://www.fifatravels.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074a6529bc06---44807539336.pdfIn PDF document text
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/16076a00a3531e---lazozuwikaxane.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_off0000d1fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1FD 11224 bytes
SHA-256: 2b6caf81ca670f1bf922117be0b6396cb07156e6ec7ea5000060c01f8f6a66b4
font_01_sfnt_off0000ec05.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC05 19620 bytes
SHA-256: 8079a27ac84f9707e5077ab983e657d5423bb75b7adb2e254899125c13e9a427
font_02_sfnt_off00011fa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11FA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1