Malicious PDF — malware analysis report

Static analysis result for SHA-256 3768b61baf4dba8e…

MALICIOUS

PDF

84.0 KB Created: 2021-09-15 22:13:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 6da10e85bac97a86f07b6bd00cea36de SHA-1: 8cbdb6316a5a6105b9eab921ef677ef460ea22f3 SHA-256: 3768b61baf4dba8ec159ae3531e650af61db2d820709f3adcc3c2fb34e10fed7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample was detected by ClamAV as a phishing trojan and flagged by an ML classifier. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm or phishing lure. The presence of embedded URLs and the PDF_SEO_DISPOSABLE_LINK_FARM heuristic strongly suggest the document's purpose is to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://coherence.cz/userfiles/file/mutojuduxiw.pdf In PDF document text
    • http://sualpturizm.com/userfiles/file/40839663503.pdfIn PDF document text
    • http://ducnhua.com/upload/files/fakeranisurod.pdfIn PDF document text
    • http://seritour.com/rsm/files/51080146601.pdfIn PDF document text
    • https://andhimazhai.com/images/files/ziwez.pdfIn PDF document text
    • http://tpdw.pl/userfiles/file/34503102316.pdfIn PDF document text
    • https://solelane.com/ckfinder/userfiles/files/tajaga.pdfIn PDF document text
    • http://popeyebio.com/upload/files/neganofuxedamodo.pdfIn PDF document text
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16137e4a794543---29668174239.pdfIn PDF document text
    • http://djapm.com/userfiles/file/tuxuxijonitumobapoxekis.pdfIn PDF document text
    • http://gursakaryahukuk.com/images/file/95236538219.pdfIn PDF document text
    • https://kaptenhoki.org/contents/files/19178559359.pdfIn PDF document text
    • http://mobilahomedesign.com/userfiles/files/55438974364.pdfIn PDF document text
    • http://dnepropress.net/files/file/xivepupepuranisevufovale.pdfIn PDF document text
    • http://parikshitconstruction.com/uploads/90337348449.pdfIn PDF document text
    • http://harrodsrentacar.com/public_html/userfiles/file/zutufeke.pdfIn PDF document text
    • https://sandp-engineering.com/ckfinder/userfiles/files/77636466146.pdfIn PDF document text
    • http://baodieptailor.com/uploads/2021-09-13/images/files/39791526976.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613dcc907f464---18572497311.pdfIn PDF document text
    • https://neurondevelopment.org/userfiles/file/melejibobajado.pdfIn PDF document text
    • http://gardensyellowcab.com/admin/images/file/83191558357.pdfIn PDF document text
    • https://thewentworthco.com/wp-content/plugins/super-forms/uploads/php/files/2bjp6gc603b70qjabn095b3bh8/gemazifoliwenosusiz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=call+of+duty+modern+warfare+4+apk+downloadPDF 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_off0000dfc5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC5 19064 bytes
SHA-256: de05e81141a211c932fce22ae8c74d8491de5119a063f16a9354e7f49d93bdf4
font_01_sfnt_off000110c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000128e0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x128E0 10900 bytes
SHA-256: 8bc5851e0804deee99a247caa0d6dcf0ca2bda914df8adc27937ce1d1490fd31