Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf37850043df10d1…

MALICIOUS

PDF

89.9 KB Created: 2021-07-15 12:59:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 158e9f3a3b2306015834ca348f773401 SHA-1: b47fff174cabe9d918cf4c3d7864c41c3b2f7500 SHA-256: bf37850043df10d1e02360942fc61366d45346d0a2c9163b7ac576e99811aad6
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. Heuristics indicate it functions as a link farm, directing users to multiple compromised WordPress sites and disposable hosting domains. The embedded URLs suggest an attempt to distribute further malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://skup-laptopow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c8fd0576ad---wibanigoxatevelepupuvelo.pdf In PDF document text
    • http://ttworld.hu/uploads/content_files/files/vesovobafotexojezobaviwuv.pdfIn PDF document text
    • http://dolphinkorea.com/files/files/25637445470.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/naninitisamikolitasut.pdfIn PDF document text
    • http://mfcwestenkwartier.nl/beta/userfiles/file/mijoravonepevotev.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160afce2ec5de8---sazek.pdfIn PDF document text
    • https://jdrum-music.com/uploads/ckfiles/files/bepudasasupazavorosupo.pdfIn PDF document text
    • http://orderkiwicafe.com/uploads/files/83325702482.pdfIn PDF document text
    • https://capecoralliving.com/media/file/jisonugofepubetusanerux.pdfIn PDF document text
    • http://aldercrest.com/files/siwujanidalutivej.pdfIn PDF document text
    • http://bochosushi.com/wp-content/plugins/formcraft/file-upload/server/content/files/16090e1e65f7da---fepazepatijexuluzatizu.pdfIn PDF document text
    • https://adm.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/ee3406179b9e5162ff191e6fb92663d3/jivif.pdfIn PDF document text
    • http://kath-kiga-bw.de/bilder/berichte/file/jazikivesitipa.pdfIn PDF document text
    • http://pulsarvn.com/media/ftp/file/lemodezatubu.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160894621b1dc6---53818262700.pdfIn PDF document text
    • http://m2m2design.com/userfiles/34884839817.pdfIn PDF document text
    • http://thelonerangerfanclub.com/ckfinder/userfiles/files/dutedirizawijasuzerov.pdfIn PDF document text
    • https://advancedbusiness.co/wp-content/plugins/super-forms/uploads/php/files/7b3ecec3ffd5b8609b2c19a41c90b94f/deluwemokudatexatabekob.pdfIn PDF document text
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/218dddba8ee447078f5e41e53c5f4900/fozexejupuzabopaselo.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/h9om05ra5rk7ddtaab5bgqm714/48367985896.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b7f17de760---13776886609.pdfIn PDF document text
    • http://zjxfjc.com/uploadfiles/files/78295598858.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160743357a5a30---67820337610.pdfIn PDF document text
    • https://fasaac.org/temp//files/vodirekiz.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/v2ogs0f1kkvvr5fbel7to9r0gt/samufenoxuvu.pdfIn PDF document text
    • http://kartinatv.org/uploads/files/kafufafuza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=acute+acidosis+in+cattle+treatmentPDF 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_off0000fc7a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC7A 17344 bytes
SHA-256: 84c6436961886755ac4fe69cebf9726117534a5c295a170f3e5504d96c4c2d70
font_01_sfnt_off00012985.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12985 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001419c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1419C 10612 bytes
SHA-256: 40c13325aff018d72cf5ce766905d5003caf3f3c65b2143a73952f20f91310c9