Malicious PDF — malware analysis report

Static analysis result for SHA-256 86a9325d37fa81f8…

MALICIOUS

PDF

70.9 KB Created: 2021-09-26 11:51:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 8facfe332938634df57d4a3152b63df8 SHA-1: 24515f4958b7cf3fb295ee3bfc4daec9536a69db SHA-256: 86a9325d37fa81f8873e61cb03417531460fef3ae6d07c33dc1fcf5e1fc9901c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Several heuristics point to the document being a link farm hosted on compromised CMS uploads, with numerous unknown URLs suggesting a phishing or malware distribution campaign. The presence of multiple PDF link farm indicators and the ML detection strongly support a malicious classification.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614511e59cc45---tonixefe.pdf In PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/161366d8dbd338---furavesepubew.pdfIn PDF document text
    • https://emmaushuis.org/pages/jusudalujes.pdfIn PDF document text
    • https://vgi-vn.vn/app/webroot/img/files/5342249245.pdfIn PDF document text
    • http://mevlanaasm.com/resimler/files/gakirimiroxudufu.pdfIn PDF document text
    • https://luxartparquet.com/wp-content/plugins/super-forms/uploads/php/files/561a3724f3b96d14391d2761b187e80b/16877748443.pdfIn PDF document text
    • http://www.meglobalinc.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16131accd67e38---piwiluxosibafevisobako.pdfIn PDF document text
    • http://gorsilawfirm.com/userfiles/file/raborekogixi.pdfIn PDF document text
    • https://dbjadow.pl/attachments/file/86888328399.pdfIn PDF document text
    • http://gesht.ru/admin/ckfinder/userfiles/files/84132628706.pdfIn PDF document text
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/t26phko3s39rbqae21j828nql0/18385258547.pdfIn PDF document text
    • https://shiokuda2.com/contents/files/gitodufeni.pdfIn PDF document text
    • http://inistor.com/ufiles/files/relekixugimu.pdfIn PDF document text
    • http://erpsamik.com/ckfinder/userfiles/files/soraxoxa.pdfIn PDF document text
    • https://khmernative-rice.com/userfiles/file/59664469684.pdfIn PDF document text
    • http://smarttechsolutionukltd.com/uploaded_files/userfiles/files/35978008226.pdfIn PDF document text
    • http://huonglonghotel.com/uploads/image/files/6919331734.pdfIn PDF document text
    • http://scvumaichiramen.com/uploads/files/migilaropumew.pdfIn PDF document text
    • http://flyingwedge.com/uploads/assets/file/delexijojowuzonegomuxama.pdfIn PDF document text
    • http://ourdesign.hk/ckfinder/userfiles/files/10251388915.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/a770e77af5798b986d75e953565b4b3f/98537495567.pdfIn PDF document text
    • http://ipcmanpower.com/admin/style/images/userfiles/file/1079501676.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=best+zombie+games+on+play+storePDF link annotation
    • http://s292376414.onlinehome.fr/datas/imgmail/file/80280534490.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_off0000b093.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB093 10964 bytes
SHA-256: 3405a675472f540e0703710d6443cfcd3745b165f922b25117c83c4a6154fa02
font_01_sfnt_off0000c9e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC9E1 16892 bytes
SHA-256: 32dfe116977619b47576753d5c569cf9f5c08a70a710142942129bb8c027811e
font_02_sfnt_off0000f5c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1