Malicious PDF — malware analysis report

Static analysis result for SHA-256 10cfd6251e611829…

MALICIOUS

PDF

81.6 KB Created: 2021-09-02 15:10:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 10dbbbc68749cbb25d3d50f0474427bf SHA-1: f0a9480c037f0cc4b840191456df1f168f44e5d8 SHA-256: 10cfd6251e61182907ff151e5f96fd05b94bde35ff4d486005c0f61a1260c344
156 Risk Score

Malware Insights

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

The PDF document contains numerous links, many of which point to compromised WordPress sites and disposable hosting domains, indicating a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, but the heuristic firings clearly indicate a malicious link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.helmmsp.ca/wp-content/plugins/super-forms/uploads/php/files/a21be7395aaecf8e600887f5ba3ea358/50165737581.pdf In PDF document text
    • http://grupomarsamo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a76a7948a0f---liwipezojij.pdfIn PDF document text
    • http://hattrick-sports.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f05c27bee1---pejilubetenuru.pdfIn PDF document text
    • http://shethof.ch/cgi-bin/dynamisch/file/muzagibedova.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/16099047a6032f---bubusanop.pdfIn PDF document text
    • https://fivetc.net/uploads/files/tikenepunexebazobilol.pdfIn PDF document text
    • https://soechi.id/userfiles/file/gonogubijagewowuzokip.pdfIn PDF document text
    • http://old.bgk-meshkova.com/ckeditor/ckfinder/userfiles/files/98431408697.pdfIn PDF document text
    • https://lightspec.com/wp-content/plugins/super-forms/uploads/php/files/2d34450aafbe67cab0645a04612bb682/vuguwawekekisukoli.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160816d1305a23---30496016464.pdfIn PDF document text
    • https://yucekalipmakina.com/tsrm1/img/userfiles/file/50671075365.pdfIn PDF document text
    • http://ahcxdq.com/uploads/file/281211357114.pdfIn PDF document text
    • http://www.kliningstroy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160e5162622773---guxifelozuwexipomowej.pdfIn PDF document text
    • https://xanbiente.de/userfiles/file/nonaxiwufexelidakavowezu.pdfIn PDF document text
    • http://print-printonline.com/ckfinder/userfiles/files/karowuvufesekuxozewomi.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/16817295146.pdfIn PDF document text
    • https://avgdesign.com/userfiles/file/kugepasazugulalazo.pdfIn PDF document text
    • https://feniks9.ru/ckfinder/userfiles/files/78431352305.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/jezogu.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/ov1mtj6ktf01rbq5jelduf6tl3/tevakem.pdfIn PDF document text
    • http://liccuza.ro/stiri_files/file/kibadivobagenifeg.pdfIn PDF document text
    • http://umrllc.com/userfiles/files/89686640182.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b05b1941686---rororivefev.pdfIn PDF document text
    • http://herningbadintra.dk/app/webroot/upload/files/80259355431.pdfIn PDF document text
    • http://podiummoda.ru/userfiles/file/funaxikonidugukemidu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=manual+de+organizacion+de+una+empresa+peque%C3%B1a+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_off0000d50f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD50F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED26 11368 bytes
SHA-256: 3b59bf99cf933fd5595c3b7a631d37fbb6b34b86bb43d49553079f6445d19aa2
font_02_sfnt_off00010717.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10717 18292 bytes
SHA-256: b8f79b35dff0dad13559e516b73712a978273b687b94af68239bdf8fb9462e18