Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7dd6a718366759b…

MALICIOUS

PDF

124.4 KB Created: 2021-09-08 19:52:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f7317d684c4d9a1553d42f0121c769e2 SHA-1: f915e14682c11726c6fb90908aac24939566dfc0 SHA-256: a7dd6a718366759bd1196d438366e031469fbfb00a30cc011ba86c13545d5aa1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous external URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of PDF-specific heuristics like 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' reinforces the conclusion that this PDF acts as a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9957

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://cructi.ru/uplcv?utm_term=csiro+diet+book+pdf PDF link annotation
    • https://hkparkkonutlari.com/image/files/mipobizawudijivezeza.pdfIn PDF document text
    • https://kimtuong.vn/isc/public/files/fckupload/file/21951486885.pdfIn PDF document text
    • http://xn--80aafjbawrcdgsodbdciig4a5v.xn--p1ai/pict/file/gonutekifefexep.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130709930a81---7542097576.pdfIn PDF document text
    • http://www.diplomat2014.ru/ckfinder/userfiles/files/figadopegiwil.pdfIn PDF document text
    • https://itscebu.com/upload/file/20210902235730.pdfIn PDF document text
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/pakemaja.pdfIn PDF document text
    • http://tischtennis-kiel.de/images/file/41610541467.pdfIn PDF document text
    • http://www.vandiestbrandstoffen.be/uploads/files/lulupovetixuwakarik.pdfIn PDF document text
    • https://dananeye.com/uploads/files/202109070303194717.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/ea40dbbed1a0fa18937219260f7585e8/komekurapu.pdfIn PDF document text
    • https://talenthunt.biz/userfiles/file/risodavofero.pdfIn PDF document text
    • http://ovecollection.com/royal/admin/images/products/file/47857276581.pdfIn PDF document text
    • http://floralojistik.com/userfiles/file/temimasakan.pdfIn PDF document text
    • http://vamaconsulting.sk/userfiles/file/55964161651.pdfIn PDF document text
    • http://extreamtuning.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16135ca61a3fcb---pajewaxozuwiwokuwuvo.pdfIn PDF document text
    • http://sanitaerprofi.ch/fckeditor/editor/images/file/woxapegasabidakogipesew.pdfIn PDF document text
    • http://www.mueblesgamez.com/ckfinder/userfiles/files/dikawako.pdfIn PDF document text
    • https://pisangmanis.com/contents/files/zebekajemewopose.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/00bcdb46f2db28e0fc7c9ce81fc329f2/55264659097.pdfIn PDF document text
    • https://artesapanaderia.xyz/aym_image/files/lemibujipu.pdfIn PDF document text
    • https://777mto.org/contents/files/waromuvejonet.pdfIn PDF document text
    • https://kocarbonag.com/luutru/files/zosotema.pdfIn PDF document text
    • http://esejsc.com/upload/files/getikepakolozejofe.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_off00017c68.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17C68 10444 bytes
SHA-256: 089eedafd1d209769e6384884a15094473edb69be8b7ba7798b5d55023f28155
font_01_sfnt_off00019409.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19409 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001ac1b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AC1B 21136 bytes
SHA-256: 892c310a6a9d6bfeaaf2c4d06576acac0f80788eee4aa447921fa8b4cb1ba809