Malicious PDF — malware analysis report

Static analysis result for SHA-256 171d34c2ff65c84f…

MALICIOUS

PDF

81.1 KB Created: 2021-09-14 14:07:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 60a0def843166b0188f5db8e85f8ccf1 SHA-1: bc6cc81c41716781bb9e438b1864116d3e558154 SHA-256: 171d34c2ff65c84f445bb8ab139881376093e7dd22b942f6f4ff4c3274f3da81
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

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 distinct hosts, some of which are hosted on compromised CMS uploads or disposable domains. The embedded URLs suggest an attempt to redirect users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://katour.ru/admin/ckfinder/userfiles/files/84997480377.pdf In PDF document text
    • https://itscebu.com/upload/file/20210908193533.pdfIn PDF document text
    • http://laboratoriologos.it/userfiles/files/libazezibu.pdfIn PDF document text
    • http://kleiberit.ru/files/file/94945937961.pdfIn PDF document text
    • http://nifaelectronics.com/userfiles/file/zezepewefuvupotewixe.pdfIn PDF document text
    • http://abpjseah.news-read.com/upload/files/94343579533.pdfIn PDF document text
    • http://tlxzkj.com/uploads/file/131833175144.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1613ecee7b25ab---wurozogogemazide.pdfIn PDF document text
    • http://sonnenheizungen.ch/fckeditor/editor/images/file/10265878926.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e82d6424b8---dewik.pdfIn PDF document text
    • https://eurosan.pl/user_images/file/gobukurino.pdfIn PDF document text
    • https://sinarwaja.com/account/files/fokopofoxujofugu.pdfIn PDF document text
    • http://xn--80aafkqcanfpgnhbng3b5i9a.xn--p1ai/pict/file/dosofefejodo.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/35176096095.pdfIn PDF document text
    • http://hrjok.com/uploadfile/file/rugisobamumedozoxurek.pdfIn PDF document text
    • http://canxetaianhduc.com/images/file/5418150216.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613af92c6e43d---soxazeweran.pdfIn PDF document text
    • http://westpakusa.com/phpsites/vertical_living/uploads/file/fixuduzewelotemulomuzeki.pdfIn PDF document text
    • http://gamax-motor.cz/data/dokumenty/34799666151.pdfIn PDF document text
    • https://spheresignal.com/app/webroot/userfiles/files/44353382562.pdfIn PDF document text
    • https://adtw1.elfjane.com/ckfinder/userfiles/files/gekij.pdfIn PDF document text
    • http://bjsddesign.com/filespath/files/20210901135844.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fad17f3856---wazuxajeloxixeninodep.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=how+to+change+status+bar+icon+color+in+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_off0000d58a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD58A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed9c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9C 18304 bytes
SHA-256: bb7a6e998c547254210ae14c6480c94342aa7ad68de70cca94c12a7fb6207859
font_02_sfnt_off00011d67.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D67 10964 bytes
SHA-256: 12f06f0e011b7e5092e3df5be605840555b9dec6fa904d1f6890a1d17c0c4406