Malicious PDF — malware analysis report

Static analysis result for SHA-256 8a9efcb8010891e3…

MALICIOUS

PDF

90.9 KB Created: 2021-09-07 23:24:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 29911471b0cc006eb115cc9218b76d05 SHA-1: b3f4be5378c46d18e0e493778cec514d03394857 SHA-256: 8a9efcb8010891e3f04e12b4affc268c60029b76620b593a00ecb604f85e234b
156 Risk Score

Malware Insights

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

The sample is a PDF identified as malicious by ML classifiers and ClamAV, specifically flagged as a phishing trojan. It functions as a link farm, containing numerous URLs that point to compromised WordPress sites and other hosting, likely intended to lure users into downloading further malicious content. The PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristic indicates a pattern of using compromised content management system uploads for hosting malicious files.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160ac1b6709573---subitasiberadigo.pdf In PDF document text
    • http://www.mywil.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160aaf7ba81568---fopidiserup.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e60b7a8a79---tutefinamidigixudekufari.pdfIn PDF document text
    • https://africanresearchcenter.com/userfiles/file/gafeler.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b2a1c27fa00---lodobozitudirafegutideja.pdfIn PDF document text
    • https://majubesar.info/contents//files/802205125.pdfIn PDF document text
    • https://brunoamaranti.it/wp-content/plugins/super-forms/uploads/php/files/h2gtsl4e8eoma4h5kvm038cbp1/zamogasesafuvuzub.pdfIn PDF document text
    • https://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/936144aaeee29a7cdc5de312f29ad459/80580522992.pdfIn PDF document text
    • http://turnwealthy.com/ckfinder/userfiles/files/2337338248.pdfIn PDF document text
    • http://zatoodesign.com/userfiles/files/14082176743.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/13342945824.pdfIn PDF document text
    • https://chaplains-camps.org/upload_picture/file/2139216887.pdfIn PDF document text
    • http://seashoresilverlabradors.com/clients/4/48/482fd9669fb3260065120a60ccac5e48/File/ralidokevexegozifowo.pdfIn PDF document text
    • http://anhhieu.vn/hinhanh/file/6831659237.pdfIn PDF document text
    • https://whitesal.com/data/images/file/8345_20210518074715.pdfIn PDF document text
    • http://accessiblevehicleservices.com/userfiles/file/vewugiboguroxixow.pdfIn PDF document text
    • http://www.driftime.ee/wp-content/plugins/formcraft/file-upload/server/content/files/160d3d75524fbc---nuvuviweja.pdfIn PDF document text
    • http://shopcloud.cloud//ckfinder/userfiles/files/jivaradupefikopela.pdfIn PDF document text
    • https://www.privathospitaletkollund.com/ckfinder/userfiles/files/vegoviradoxujiselitisi.pdfIn PDF document text
    • https://ktmcollege.org/public_html/userfiles/file/27928154443.pdfIn PDF document text
    • http://www.associatedomains.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b111023eb8a---94752452480.pdfIn PDF document text
    • http://intestinalfortitude.org/clients/0/0c/0cf504f131cb0201443a7bd449519f4a/File/4760343457.pdfIn PDF document text
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/82590e088d871c166431343c3443849e/poroxidixivudenefekoduwim.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/2663232757.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=split+pdf+pages+by+contentPDF 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_off0000ff26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFF26 11024 bytes
SHA-256: 47b2146c1e75fa901e188a3368d93ce3f1049e4f4d6dd949ddd988c84a2c9ea1
font_01_sfnt_off00011883.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11883 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013095.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13095 17840 bytes
SHA-256: f63c6f730ab3ebb7197ae680596373bde659c4802d81abbdedcb00b1b7640b11