Malicious PDF — malware analysis report

Static analysis result for SHA-256 839ecd42498b86cc…

MALICIOUS

PDF

93.3 KB Created: 2021-08-06 11:50:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ec839b11bd8d1d467388287c5be3dfad SHA-1: 219f7ba426b2a2328c87ca5bf979edf5e0b0489e SHA-256: 839ecd42498b86cc045a50412e852c7986b0cdd151bff5b702295355c37404ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. The document contains a link farm with numerous URLs pointing to other PDF files, many hosted on compromised CMS uploads. This suggests a tactic to distribute malicious content or engage in SEO poisoning to lure victims.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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 http://kingsfinancialconsulting.com/userfiles/file/lapasizafapetukaramug.pdf In PDF document text
    • http://automsystem.com/UploadFile/file/20210713035945091.pdfIn PDF document text
    • http://donaldnathanlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/49722576611.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/98a8f73e603df526de44b7948def7e9a/59219056754.pdfIn PDF document text
    • https://palet-school.com/files/files/53279005136.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/fnragkcvjoo9jbgkim9ku2uuj4/83767009748.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/kucleb6ktvf9fn9729ml0ns6mo/kanedumodabivesomoj.pdfIn PDF document text
    • http://asr-net.ru/uploads/files/norux.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/gv63rs9rkv3qh57q1161hid9m0/vaxuzivajak.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/sutedasi.pdfIn PDF document text
    • https://www.sixteengrams.com/wp-content/plugins/super-forms/uploads/php/files/hakaiq0ul0iqf86qo9iv2h2nnc/32461960298.pdfIn PDF document text
    • http://goldmustang.com/files/files/fonubalevusitomozut.pdfIn PDF document text
    • https://a2designbg.com/userfiles/file/57205605092.pdfIn PDF document text
    • http://dobre-jaja.com/Upload/file/kelexufusopofaretuvokini.pdfIn PDF document text
    • https://jmtours.co/aym_image/files/98430589433.pdfIn PDF document text
    • http://westtech1963.com/clients/d/d4/d4250bc21dcbbf02d7f9bc68df143add/File/19904550887.pdfIn PDF document text
    • http://sccsfz.org/upload/favotomage.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a75be8029ef---xajamalupefa.pdfIn PDF document text
    • http://stalmont.eu/userfiles/file/9794345070.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/luxopimo.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/50474375450.pdfIn PDF document text
    • http://juentai.com/userfiles/files/gerobigapevarorub.pdfIn PDF document text
    • http://carrozzeriardue.it/userfiles/files/nefewodoxonofuwireralapet.pdfIn PDF document text
    • http://timatey.kz/wp-content/plugins/super-forms/uploads/php/files/1i7u6q5ahuo2eddtkb4sjq1ek6/22099775619.pdfIn PDF document text
    • http://cityfate.com/files/files/53235702388.pdfIn PDF document text
    • http://dejede.com/userfiles/file/xulimawijipane.pdfIn PDF document text
    • https://qqhanoman.com/contents//files/22578343596.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+check+if+your+turbo+is+badPDF 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_off000106d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106D6 10944 bytes
SHA-256: 59bc05f4e29e0b3d21a2cfaf6d3af399c1b6c2f089eb9729f0534e855ee00a8c
font_01_sfnt_off00012067.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12067 18116 bytes
SHA-256: eccfcd3f5e6b89c1d9a42ba2f616fd5fff5f526a68d3ecd52d614668119b4a88
font_02_sfnt_off00014ece.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14ECE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1