Malicious PDF — malware analysis report

Static analysis result for SHA-256 0872633ae4f64038…

MALICIOUS

PDF

70.2 KB Created: 2021-09-26 22:44:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 818eca78e08ac3426e97d0592c75eeb9 SHA-1: 101fcb9cb8bae36d738639c555b150707618be5b SHA-256: 0872633ae4f640383a9b13aae91d0ef944d0e07a61e278775d6451deb1f8f6dd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristic analysis indicates it functions as a link farm, directing users to multiple potentially compromised websites. The presence of numerous external URIs, many hosted on disposable domains or compromised CMS uploads, strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://horvathortho.hu/tmp/kifanaxinabesixuzubazore.pdf In PDF document text
    • http://hometextiles-consultant.com/ckfinder/userfiles/files/xepovivurujuvulujiker.pdfIn PDF document text
    • http://cnsgawefgl.netsociality.com/upload/files/tutulebenemusedabidaka.pdfIn PDF document text
    • http://ecohost.ru/pics/images/file/zijulonetewekesimap.pdfIn PDF document text
    • http://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b503b36389---lotavuzoke.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/16130aaf5ccbd1---lexebaxawuwawazodin.pdfIn PDF document text
    • http://ei-windykacja.pl/upload/file/82094118825.pdfIn PDF document text
    • http://www.zav-mito.si/wp-content/plugins/formcraft/file-upload/server/content/files/1614998142e149---pubifuvidafilafa.pdfIn PDF document text
    • http://www.huescalamagiaenfotos.com/userfiles/files/jugipuforitin.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16144b5c58fd3f---dodetidolixuxazaximi.pdfIn PDF document text
    • http://hueide.com/upload/files/riduz.pdfIn PDF document text
    • http://gnatowski.pl/attachments/file/pumajukexuredanaxosofu.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/10125923878.pdfIn PDF document text
    • http://kastely-vacduka.hu/fileok/file/gukiruga.pdfIn PDF document text
    • https://marlin-aquarium.ru/ckfinder/userfiles/files/85803999343.pdfIn PDF document text
    • http://optimaglobal.net/ckupload/files/vipetojolujujuxuwutelu.pdfIn PDF document text
    • http://yugang360.com/upload_fck/file/2021-9-15/20210915174844192107.pdfIn PDF document text
    • http://farmaciafoglia.eu/userfiles/files/86500742375.pdfIn PDF document text
    • https://duongthuy.net/userfiles/file/xojimeno.pdfIn PDF document text
    • http://zamdq.com/filespath/files/20210904012700.pdfIn PDF document text
    • https://dollarplus98.com/images/upload/files/83563261669.pdfIn PDF document text
    • https://mimpiindah1.com/contents/files/xatenilapo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=android+tv+close+appsPDF 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_off0000afdf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAFDF 17336 bytes
SHA-256: 345baa992d7d725ad9fc3f505b72a8a9c61f12798791bda532da56462130b1bc
font_01_sfnt_off0000dba9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f3c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3C0 10556 bytes
SHA-256: 0dad21e31f6aec1decb88efc651cf1505c1540c255123ec9c5efa191ca79e9e0