Malicious PDF — malware analysis report

Static analysis result for SHA-256 16839201d628d61b…

MALICIOUS

PDF

85.9 KB Created: 2021-09-09 02:38:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 0ed1af4c934bca91b0fe2b33fdd5d933 SHA-1: 29728c78c38e5dfb6ab9f63b9aef9473c09df8e6 SHA-256: 16839201d628d61b2d86a9a4a637f4ed1d8486f7e0617a150a4d61ce73812f79
156 Risk Score

Malware Insights

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

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 external websites, some of which are hosted on compromised CMS uploads. While no scripts were directly extracted, the nature of link farms in PDFs often involves embedded JavaScript to facilitate redirection, hence the inclusion of T1059.007.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://patronusalapitvany.hu/public_html/upload/30578114372.pdf In PDF document text
    • http://retailcop.ca/files/82671971358.pdfIn PDF document text
    • http://stluciachamber.org/uploadedImages/contentImg/file/71086166880.pdfIn PDF document text
    • https://duproject.com/uploadEditor/files/48717325949.pdfIn PDF document text
    • http://fruitsad.pl/images/file/97551347207.pdfIn PDF document text
    • http://piemonteforyou.it/userfiles/file/75706683354.pdfIn PDF document text
    • https://tungafilm.com/dorceiys/ckfinder/userfiles/files/wubifamab.pdfIn PDF document text
    • http://phutungototuanphat.com/img-tvdl/files/43371715100.pdfIn PDF document text
    • http://barrybusiness-crm.com/ressource/devis-photo/files/somexi.pdfIn PDF document text
    • https://www.truck-transport.com/ckfinder/userfiles/files/36121440091.pdfIn PDF document text
    • http://airzo.net/userData/board/file/70429756753.pdfIn PDF document text
    • https://12shio1.com/contents/files/76333071589.pdfIn PDF document text
    • http://studiogiovannone.com/userfiles/files/jugejofuzejopuf.pdfIn PDF document text
    • http://atek-ent.com/upload/file/fozotewuxatukelafedagoz.pdfIn PDF document text
    • http://www.advancedevents.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16137d7ffc83e8---poguxola.pdfIn PDF document text
    • http://mvdeastudio.it/userfiles/files/newalofogisujomuve.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/99951681981.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132ffca2bafc---65421724209.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/befotizusade.pdfIn PDF document text
    • http://tzsunup.com/upload/19917438143.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/44303791951.pdfIn PDF document text
    • http://www.asiacoservice.com/file/files/60842263128.pdfIn PDF document text
    • http://intechsol.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1613759b391304---bukogifobelolugitixol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=top+10+pc+emulator+for+androidPDF 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_off0000ecfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECFB 16784 bytes
SHA-256: b756b142ec7a0aabdbfcc9cf6ad3b95b8768e10b559224fd3f130962b3a437ca
font_01_sfnt_off0001186a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1186A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013081.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13081 10848 bytes
SHA-256: fabcc97702592fa8e2101e3de82f1aaa93e17c6ba9eba2efaa149e6fa4113683