Malicious PDF — malware analysis report

Static analysis result for SHA-256 20e8c8816c327f00…

MALICIOUS

PDF

94.0 KB Created: 2021-08-04 20:25:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-23
MD5: 81535dae3007645534e612c8ed2ee7d6 SHA-1: 40bad80aabf07a1ed5de6d894364fbb21808913d SHA-256: 20e8c8816c327f008e12b874838c52131a8707a2c0989625803241c55811362a
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. Heuristics indicate this is a link farm designed to redirect users to other malicious PDFs hosted on these compromised sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9988

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.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c41c8403df---pudikipasisele.pdf In PDF document text
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/48400f1e61bea482ead452bb449c5dc9/nikikudobereguwisole.pdfIn PDF document text
    • https://simovi.mx/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4891e6651---53043066878.pdfIn PDF document text
    • https://askisan.com/upload/ckfinder/files/47794897088.pdfIn PDF document text
    • https://maconlux.lu/userfiles/files/72680009823.pdfIn PDF document text
    • http://agrobud.net/uploaded/file/83351770358.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/900c8bf04db76925c9136f451136c781/witemuvubozanader.pdfIn PDF document text
    • http://vorne-sitzen.eu/pcms/content/file/wujagovafinixixegopedifip.pdfIn PDF document text
    • http://hagelkonzept.de/userfiles/file/zavigulugiroveteti.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/a0c9a6bec30277fbb94d155fe336fdd3/61597304301.pdfIn PDF document text
    • http://booklandbooks.com/userfiles/file/rewuxagebetetepa.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/29065408754.pdfIn PDF document text
    • http://usmleworkout.com/files/file/zalikug.pdfIn PDF document text
    • http://ambulatorioveterinariomariani.it/userfiles/files/japokalusowav.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a386df4630e---34762123279.pdfIn PDF document text
    • https://firesystem.ro/imagini_ws/sudawidoziwerijumexek.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/fd768260e2e0f3e2cd033539c9bf82f0/faxelenifunekilogupo.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/161086ea48767e---79598305246.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16097492045a4d---kuzojarife.pdfIn PDF document text
    • http://microsolder.hu/userfiles/files/78922578046.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=9+regiones+abdominales+del+cuerpo+humanoPDF 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_off00010746.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10746 11172 bytes
SHA-256: 0c7b8a0dd70f2ee5576d2cbf2e3f6fc4ddd1897adf516623a6831a3f70481b3c
font_01_sfnt_off000120bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120BC 18528 bytes
SHA-256: b26dac2a53194caae9150cdd9952786f6bca4045323b294cdb19a5ab071c60b0
font_02_sfnt_off0001503c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1503C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1