Malicious PDF — malware analysis report

Static analysis result for SHA-256 7cb91c49b6d9bb3f…

MALICIOUS

PDF

88.7 KB Created: 2021-06-25 18:12:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 46fb05f0bb16b7144e0a901813f4a412 SHA-1: 680f1621b9829666e27821dc5e899dda83e382a4 SHA-256: 7cb91c49b6d9bb3f1173f28543158f0e819f3549ca59bd7dc3e5a4351496c0e3
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm hosted on compromised CMS uploads and disposable hosting, pointing to phishing or SEO abuse. The embedded URLs, while some are marked benign, are part of a larger network of links suggesting a coordinated effort to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://www.finanzanlagen-honorarberatung.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609eecadb473d---26659906545.pdf In PDF document text
    • http://banghaija.com/userfiles/file/teziz.pdfIn PDF document text
    • https://erinmillssmilesdentistry.com/wp-content/plugins/super-forms/uploads/php/files/v0hlam9osk47b0k6e2g5spa5v5/ketoz.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/5f6add0e3cbc42b5c59277e47f96998e/kesuxofaketidebati.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075f6f07caf0---moxilajipepujojomitat.pdfIn PDF document text
    • http://termitecontrolservicebd.com/ck/upload/files/14263243103.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607ffcf1f1f19---37906260124.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/e04617851192595fc4587e71ca06573f/41345202054.pdfIn PDF document text
    • https://go2germany.ru/files/file/bekene.pdfIn PDF document text
    • https://www.dolphinrfid.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091b08b408bc---65046615655.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5f1af09fe9---pozixobiporu.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16075a51690523---rovapisitu.pdfIn PDF document text
    • https://www.conkite.com/wp-content/plugins/super-forms/uploads/php/files/446bf1cc6eb1f7a025d394c24844abcd/sonolizofalese.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/hfh4q5d3rb1kee4oha11e8bctq/19051782696.pdfIn PDF document text
    • https://joepromenshealth.com/wp-content/plugins/super-forms/uploads/php/files/29be4ec5c01dd02171389a0284ba2511/taruxakuvolukix.pdfIn PDF document text
    • https://borderpak.com/wp-content/plugins/super-forms/uploads/php/files/b0130d99111d7e2211e5a7b87e826ab9/gutilun.pdfIn PDF document text
    • https://cissud.com/uploads/ck_editor/files/57466419177.pdfIn PDF document text
    • http://goldenteriyaki.com/uploads/files/lajukawuganef.pdfIn PDF document text
    • http://audiencefertilization.com/fckeditor/editor/filemanager/connectors/php/userfiles/file/49979766669.pdfIn PDF document text
    • https://paperland.bg/uploads/file/xujevununi.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/5c19338c469665b963b3384a75cbd433/mubanatigufiso.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c5e73a2ea57---jejeberiwusorotuwezufafal.pdfIn PDF document text
    • http://fsgpj.com/upfolder/e/files/20210618034959.pdfIn PDF document text
    • https://wacee.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a766968c412---sijunabufej.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084f3b88b987---musol.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=class+12+physics+moving+charges+and+magnetism+notesPDF 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_off0000f2be.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2BE 11344 bytes
SHA-256: 5aeed7e44dcb2ac331aef5cd991a2de29226c30e3a0e943827830aa6a7338335
font_01_sfnt_off00010d38.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D38 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001254a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1254A 17540 bytes
SHA-256: bf1db0e05ecb29cdd86c4617a8701e21d16fcafcbbcb877ed6e9107a0e255bc7