Malicious PDF — malware analysis report

Static analysis result for SHA-256 de4c933ed9e45bc8…

MALICIOUS

PDF

82.6 KB Created: 2021-09-08 01:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: d1f7a9df3a433de3cd0fc3b3ca8d06dc SHA-1: 41341b1b07a8442f752f228f773e10ccff8ad864 SHA-256: de4c933ed9e45bc8b33c079dcd0a34f8605c9ae74e061a90b42cc6bbfa128f71
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL analysis are sufficient to infer a malicious link distribution pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 https://ketchas.ru/uplcv?utm_term=grammar+test+fce+pdf PDF link annotation
    • http://danfilenemd.com/clients/67744/File/danevenunofagupazojone.pdfIn PDF document text
    • http://www.nuricomuvakfi.org/wp-content/plugins/super-forms/uploads/php/files/q25u0thvvh100149s4bbejek05/81896494652.pdfIn PDF document text
    • https://pharmawell.eu/ckfinder/userfiles/files/60549516757.pdfIn PDF document text
    • https://plewmal-d.com/Uploads/files/8490364636.pdfIn PDF document text
    • http://hykylalumni.org/userfiles/1992466460.pdfIn PDF document text
    • https://maxim-catering.de/wp-content/plugins/super-forms/uploads/php/files/it7kn67vagr4v1hv1icjrav1of/21990023620.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16082a5da31a2b---80919387329.pdfIn PDF document text
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/936b0c6508a0a9957e9949a23c8e5050/30331040149.pdfIn PDF document text
    • http://notariocprietoa.com/notaria/documentos/files/xixemaboredazudogo.pdfIn PDF document text
    • http://minhledtran.com/luutru/files/8366867993.pdfIn PDF document text
    • https://zoldlepes.hu/userfiles/file/16150688489.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/newenuligi.pdfIn PDF document text
    • https://canvasations.com/wp-content/plugins/super-forms/uploads/php/files/6b7aa1bo760jaocaurbk07cp64/bemud.pdfIn PDF document text
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/2aj3fn3krv24cpus94o8cqs7t1/bubadokidezakujuzi.pdfIn PDF document text
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/fa3b65949149ff7d0e7e7b46c9978254/menez.pdfIn PDF document text
    • http://krevue.cz/UserFiles/File/xapuletanozet.pdfIn PDF document text
    • http://oishisushigd.com/uploads/files/64742183764.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611f192c24d4e---demagolikawumitovuga.pdfIn PDF document text
    • http://adance0112.com/upfile/editor/file/10299261718.pdfIn PDF document text
    • https://www.cibaospalaser.com/wp-content/plugins/super-forms/uploads/php/files/3imbkjvnigskud7jep2724guh6/lolikaduvigozak.pdfIn PDF document text
    • http://oguzlarotomatiksanziman.com/depo/sayfaresim/file/raxevubakirinibobipelu.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/27da8fc32963416f35616f7baaebe583/tikumes.pdfIn PDF document text
    • http://simonide.org/userfiles/file/gudodojosiluwiw.pdfIn PDF document text
    • http://anatolianlgs.com/userfiles/file/genolesuvunokemumib.pdfIn PDF document text
    • 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_off0000e103.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE103 10456 bytes
SHA-256: 859cb9706e7b481ac1fec5a113c258a95f62f39e3b6b26d6eb5c2d53e7b99f26
font_01_sfnt_off0000f8d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D1 16876 bytes
SHA-256: e45f0fd079e21d2789e48c652423dd2a7b4be425cf8b75f21a3d84f295cd53a0
font_02_sfnt_off00012476.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12476 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1