Malicious PDF — malware analysis report

Static analysis result for SHA-256 3fb304e2326919de…

MALICIOUS

PDF

108.4 KB Created: 2021-07-01 14:10:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 96f4a40dd7cb0042ca7bb8f25ef9f453 SHA-1: 1e0b90622f98397d861c2cf2d63073fd04f523da SHA-256: 3fb304e2326919de29b0acd3fb3809152a71bcb393dd15b615c0fc925851afca
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 a machine learning classifier indicated a high probability of maliciousness. The document contains a link farm pointing to multiple distinct hosts, many of which are compromised WordPress sites, suggesting an attempt to obscure the ultimate destination. The presence of multiple PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9921

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://southernlightingsource.com/wp-content/plugins/super-forms/uploads/php/files/7f8d9839f56615fa345449c782d2cab1/35568509610.pdf In PDF document text
    • https://harrisitalia.it/uploads/file/puwozegilupik.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c63465e0b2f---14722869657.pdfIn PDF document text
    • http://kiuruvedenlukio.fi/tiedostot/file/76042685763.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/4a2a90d7677cc9fbcfe92397608cd3b2/26332587746.pdfIn PDF document text
    • http://bendhorseride.com/userfiles/file/jidefixezepever.pdfIn PDF document text
    • http://bortran.com/upload/image/file/20210623115958.pdfIn PDF document text
    • https://getlovebooks.com/wp-content/plugins/super-forms/uploads/php/files/bfbd2dd18b61c54ad08d49e15fb6c1a7/dirotiwazuviziroronuxize.pdfIn PDF document text
    • https://inchirieriavioane.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16090be80d35f2---18648705102.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1609cc70038475---xukuzul.pdfIn PDF document text
    • http://techbis.pl/files/file/noveforikujalita.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099d1cbcccba---dunupewoxomebasazanid.pdfIn PDF document text
    • http://master-sign.ru/ckfinder/userfiles/files/povazeroneluzadi.pdfIn PDF document text
    • http://angelcabrera.com/FCKfiles/file/37561016493.pdfIn PDF document text
    • http://diagonal.org.ar/wp-content/plugins/formcraft/file-upload/server/content/files/16070638c4d8d6---wuzusanigudeda.pdfIn PDF document text
    • https://airshow-bg.com/file/40028284807.pdfIn PDF document text
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcbd08d662---wajijudem.pdfIn PDF document text
    • https://hafa-verein.de/wp-content/plugins/super-forms/uploads/php/files/47823d2a8ee19b434f70f4f58ccd30e2/22547075344.pdfIn PDF document text
    • http://3e-machinery.ru/app/webroot/filesfiles/pulutanabukosutanipil.pdfIn PDF document text
    • http://springswellness.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609620bb82ef7---xigexawitedi.pdfIn PDF document text
    • https://www.generalutilities.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608624ca9de5b---52425573557.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/liroxigada.pdfIn PDF document text
    • http://gadkowski.pl/repository/filemanager/file/pobutegowojexud.pdfIn PDF document text
    • https://www.tifdip.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bf4e307d76---82394864349.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/83627421359.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=smoke+gets+in+your+eyes+caitlin+doughty+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_off00013b57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B57 11448 bytes
SHA-256: 8274ab12dcfcb4daba8289a3c341dea372673603281f5f761dbf0291dfaea7cc
font_01_sfnt_off000155ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x155FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016e11.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16E11 20420 bytes
SHA-256: 9dc08de9c50db372971393406425bcf4ca00478278cf5683122127dd752d213a