Malicious PDF — malware analysis report

Static analysis result for SHA-256 5547c5805f766d25…

MALICIOUS

PDF

76.0 KB Created: 2021-09-09 04:28:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 846b704937fd749c7cb62e5fd3980baa SHA-1: 399b631371321119ea79b071ec92a73f0d671749 SHA-256: 5547c5805f766d25d40213306d306592c3e74864ef271ec876b597ce4bc2ec09
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially compromised or disposable hosting. The primary purpose appears to be directing users to external malicious sites, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9908

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 http://linpus.com/app/webroot/userfiles/files/66181094351.pdf In PDF document text
    • http://xn--90aoaidn.xn--p1ai/ckfinder/userfiles/files/39658549360.pdfIn PDF document text
    • http://rockpapersun.com/upload_mce_image/file/33480498017.pdfIn PDF document text
    • http://svazekobciorlice.cz/userfiles/file/92332963546.pdfIn PDF document text
    • http://webinaris.training/ckfinder/userfiles/publics/files/gigorexokesuxeja.pdfIn PDF document text
    • https://yptea.com/data/fckeditor/files/sanonofogeradotebad.pdfIn PDF document text
    • https://journeywithmypet.com/ckfinder/userfiles/files/pudepejemaxasefijufevojad.pdfIn PDF document text
    • http://nriloan.jctoursandtravels.in/files/rofewofu.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/91904464153.pdfIn PDF document text
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/161394bcaa932e---64851895544.pdfIn PDF document text
    • https://nothingbutsafetyglasses.com/userfiles/file/68088455345.pdfIn PDF document text
    • http://avandcie-automation.fr/ckfinder/userfiles/files/wesig.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612fc8355b397---busuzibegogujuwopudiroxod.pdfIn PDF document text
    • https://shastriratanchatterjee.com/ckfinder/userfiles/files/kanufe.pdfIn PDF document text
    • https://dolphinsolutions.net/ckfinder/userfiles/files/jagozirowuvawetasazolumog.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/304705810adb284405205d187a657509/lewirofewodowapamokewu.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/xepil.pdfIn PDF document text
    • https://grancom.by/upload/docs/gafofo.pdfIn PDF document text
    • http://thaoduoconline.com/userfiles/image/file/zejutitudesasozizikeru.pdfIn PDF document text
    • https://ochronaskory.pl/pliki_user/File/lojisepeseju.pdfIn PDF document text
    • http://clubesquilacoma.com/uploads/files/94056103465.pdfIn PDF document text
    • http://sindikat777.ru/ckeditor/ckfinder/core/connector/php/uploads/files/20534539184.pdfIn PDF document text
    • http://jingmingtai.com/filespath/files/20210906045823.pdfIn PDF document text
    • https://reformedgeneration.com/userfiles/file/digasurivifulosik.pdfIn PDF document text
    • http://palaciodelosnavas.com/userfiles/file/32941728549.pdfIn PDF document text
    • http://archetipoingegneria.it/userfiles/files/24070298247.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=mcent+browser+apk+modPDF 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_off0000c561.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC561 17152 bytes
SHA-256: 420c743861b58114ae1fada36f93da4be545eb581f393ef3bfa88eab656f6209
font_01_sfnt_off0000f168.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF168 10848 bytes
SHA-256: 0d3b754ac7381b1a2a5e37b6d542694c519ebc5a63293dc908c6a5aa7b2c603e
font_02_sfnt_off00010a5a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A5A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1