Malicious PDF — malware analysis report

Static analysis result for SHA-256 5194c37c4de1f345…

MALICIOUS

PDF

70.3 KB Created: 2021-10-04 08:45:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 6fbb26aad677ae5be682c4ee4e874ec1 SHA-1: 14759eefb4f097f2d16fa0f9f9139c6cbe3de88b SHA-256: 5194c37c4de1f345c421e0a0efc253a77d3541a7aabe3426a73967482a8d8732
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, many pointing to compromised CMS upload directories, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and link farm behavior are consistent with techniques used to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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 https://pistant.ru/uplcv?utm_term=frank+stagg+theologian PDF link annotation
    • https://jajugroup.com/ckfinder/userfiles/files/44266750933.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.com/ckfinder/userfiles/files/53658414413.pdfIn PDF document text
    • https://organicfertilizerproduction.com/d/files/gevoxegaxuw.pdfIn PDF document text
    • http://hongsung114.com/files/fckeditor/file/zaxuwusubasekevavop.pdfIn PDF document text
    • http://chothuexehochiminh.com/userfiles/file/lexitujobaxareg.pdfIn PDF document text
    • http://ghibms.com/userfiles/files/62618659443.pdfIn PDF document text
    • http://dealershop.es/userfiles/file/9201669235.pdfIn PDF document text
    • http://kleinschadenexpert.de/userfiles/file/dawefewifobumegefukidenof.pdfIn PDF document text
    • https://refakatci.net/userfiles/file/51663683897.pdfIn PDF document text
    • http://pronobile.com/catalog/file/41918020580.pdfIn PDF document text
    • http://tutek.eu/userfiles/file/tuxemefamituruluwefobex.pdfIn PDF document text
    • http://hujiangsy.com/upload/files/38817375550.pdfIn PDF document text
    • http://karate-talence.com/newsite/userfiles/files/11056153628.pdfIn PDF document text
    • http://argol-editions.fr/userfiles/file/duridisavizanugi.pdfIn PDF document text
    • http://lecostationery.com/files/file/rifuzikatapelisoruku.pdfIn PDF document text
    • https://afanasyev-design.ru/wp-content/plugins/super-forms/uploads/php/files/4130eea1a7b6e07a7470312fa740d406/xawoxazujelur.pdfIn PDF document text
    • http://zit-tech.com/userfiles/files/2350119544.pdfIn PDF document text
    • https://staffxrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/24640530421abba92977b271bcfd8eac/2893712849.pdfIn PDF document text
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16132c77b1f846---8067739727.pdfIn PDF document text
    • http://medrea.ru/upload/files/potiwemeremugigixekor.pdfIn PDF document text
    • https://demo-calson.garment-pro.com/ckfinder/userfiles/files/82948107218.pdfIn PDF document text
    • https://greenways.at/userfiles/file/35168355269.pdfIn PDF document text
    • http://modaxch.com/userfiles/files/18775889411.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_off0000b111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB111 10456 bytes
SHA-256: b98e8775bd2df2a4af0da79e111c8d2050d22917bca5ed243eadf18f10a13f65
font_01_sfnt_off0000c8b1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B1 16216 bytes
SHA-256: 718fe52a0449b3d58ebad4fde1ac973bc7b7ed5e8656c830343fe1dc11062358
font_02_sfnt_off0000f1bc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1BC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1