Malicious PDF — malware analysis report

Static analysis result for SHA-256 8315a09d3d5e04e5…

MALICIOUS

PDF

100.9 KB Created: 2021-09-12 07:49:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: db09a98db29679bfb8becc3fbad1326c SHA-1: 42e09c529b3c3340ebb441138a401fa139bbf0a5 SHA-256: 8315a09d3d5e04e5f09163751d39b885f4aa94a4df26219f023a01af7f724fa9
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple compromised CMS upload storage locations and disposable hosting, indicating an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, suggesting it's not intended for direct user interaction but rather to host malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

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://buffinvestment.com/upload/ckfinder/files/xifebaburuduzexupemad.pdf In PDF document text
    • https://catherinehourihan.art/wp-content/plugins/super-forms/uploads/php/files/ac1504217309c5f819b8f8bd26a0e462/43687589186.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/69473075386.pdfIn PDF document text
    • http://pension-erlkoenig.de/img/editor/file/xaduk.pdfIn PDF document text
    • http://cuboni.com/uploadfile/hong202109030936309413.pdfIn PDF document text
    • http://polyacer-ecp.com/userfiles/files/20210904_091754.pdfIn PDF document text
    • http://www.airportlimofortlauderdale.net/wp-content/plugins/formcraft/file-upload/server/content/files/16133ae2faccce---2928379239.pdfIn PDF document text
    • http://fanghsin.com/uploads/files/202109051637589746.pdfIn PDF document text
    • https://soechi.id/userfiles/file/lapafosejezexexi.pdfIn PDF document text
    • https://cashcruis.ru/wp-content/plugins/super-forms/uploads/php/files/cfe9b8ecb72eb0977325229945a37ad4/1731814176.pdfIn PDF document text
    • https://shiprapublication.com/uniformkontakt/userfiles/image/files/tefapixogutujixubo.pdfIn PDF document text
    • https://bharatceramics.in/ckfinder/userfiles/files/jizedatedimev.pdfIn PDF document text
    • http://hud101.vn/webroot/img/posts/files/woxujotepig.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/76764949993.pdfIn PDF document text
    • http://exteractif.fr/pictures/2/11429386558.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613427012bda5---1601796908.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/86458141804.pdfIn PDF document text
    • http://exhibitionchannel.com/upload/70366190699.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf2852efb2---kegizozedubesuvurarodobiv.pdfIn PDF document text
    • http://magiepourenfants.com/images/mediamanager/file/60962136126.pdfIn PDF document text
    • http://www.patricktennis.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16131dc8f28a04---46113462154.pdfIn PDF document text
    • http://liebherr-tr.com/userfiles/file/vakuvorinewusowosiz.pdfIn PDF document text
    • https://afra24.com/basefile/afra24/files/xakazogemega.pdfIn PDF document text
    • https://hkpefa.org/editor_upload/file/pumodiwujariseza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=pes+2004+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_off000124d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x124D8 10420 bytes
SHA-256: bdc17c7cd607e2eae927f8bd5f34d1bf81c90c8e8cb18cad95af78f548cf37ba
font_01_sfnt_off00013ca6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13CA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000154b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x154B8 18680 bytes
SHA-256: aa85b0d653466c78adc35044191237ce15fc03dc9789cc754360e6c7e6c914b6