Malicious PDF — malware analysis report

Static analysis result for SHA-256 7b3b4b6d511473a3…

MALICIOUS

PDF

89.8 KB Created: 2021-09-20 13:18:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 33dab4ae52011229bb5ddf40b63eb192 SHA-1: da497762959df922f6ba58d792e48fec57c3201b SHA-256: 7b3b4b6d511473a3295a4d0df5ea8925e268cd960eeb293af004996a28a134d0
156 Risk Score

Malware Insights

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

The PDF was flagged by ClamAV as 'Pdf.Phishing.Trojan' and ML classifiers indicated a high probability of maliciousness. Heuristics identified it as a link farm pointing to numerous PDF files hosted on compromised or disposable domains, suggesting a phishing or SEO poisoning campaign. No scripts were extracted, but the overall structure and URL patterns are indicative of malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://ahreco.com/uploads/news_file/nofudonaxuwusulusipud.pdf In PDF document text
    • http://myjobcareer.net/userfiles/file/2021090618012973499.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/0ubvhqindhr3e9l05s76n646t0/nemojatajikamopimeroma.pdfIn PDF document text
    • http://akekaluck.com/ckfinder/userfiles/files/5078909471.pdfIn PDF document text
    • https://valeaflorilor.ro/img/uploads/file/malipekoxos.pdfIn PDF document text
    • https://spirit-legend-enterprises.com/webroot/editor-uploads/files/sumitig.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/18b858665be964e1eca54ea9abe01005/fefitusa.pdfIn PDF document text
    • http://www.madiran-cruduparadis.fr/ckfinder/userfiles/files/jalodaputexuvil.pdfIn PDF document text
    • https://ladangmimpi2.com/contents/files/43856413569.pdfIn PDF document text
    • http://hosungtour.net/FileData/ckfinder/files/20210905_5BE9C88B00300D90.pdfIn PDF document text
    • http://chiaranannini.com/userfiles/files/jelaso.pdfIn PDF document text
    • http://shangrilayunnan.com/ckfinder/userfiles/files/voneguburofo.pdfIn PDF document text
    • http://dsagco.com/Upload/file/10509829283.pdfIn PDF document text
    • http://hkxhjfc.ltd/uploads/files/20210917231417.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/fawoke.pdfIn PDF document text
    • https://diedacorporation.net/freesiafiles/file/xamiwifixoxunel.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1613f970c9cea4---banagipegiropoze.pdfIn PDF document text
    • http://studiocommercialedelpiano.it/userfiles/files/4423377222.pdfIn PDF document text
    • https://mehreganimaging.com/images/upload/files/12626762193.pdfIn PDF document text
    • http://esejsc.com/upload/files/rimexurimef.pdfIn PDF document text
    • https://magicdiscoradio.com/userfiles/file/kowiwapupoxojavonukidulo.pdfIn PDF document text
    • http://omegapizza.net/uploads/files/padubixanumomakisav.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/kanufe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=formulacion+de+hipotesis+pdfPDF 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_off0000fa82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA82 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011299.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11299 10960 bytes
SHA-256: 82b41ebdc6c9a76b02c6db016a4e0092cd2723533632c839552766f7914d436b
font_02_sfnt_off00012bc7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BC7 17984 bytes
SHA-256: c7049de13bd92b02e8c29ca3bfc801907fcd682fdb9e2c1ee86864255ca3e1d9