Malicious PDF — malware analysis report

Static analysis result for SHA-256 b83fb78e40e09ad0…

MALICIOUS

PDF

84.8 KB Created: 2021-09-18 11:56:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 29580d8d7276245834f021a628b89274 SHA-1: 35d2594b7975ab18ecd2be161f14eed84a57d5c3 SHA-256: b83fb78e40e09ad051120263dac6d58fb879e6a804e40372715c8b9150d6cee3
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://triatlonshop.cz/userfiles/file/89960481541.pdf In PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/32244958086.pdfIn PDF document text
    • http://orderbestwings.com/uploads/files/fixazuwerodejika.pdfIn PDF document text
    • http://iccj.jp/images/uploads/fckeditor/file/wasivusujejumeliti.pdfIn PDF document text
    • http://hermanosgolbano.com/admin/fckeditor/editor/filemanager/connectors/phpfile/fesadiradusudajevovagife.pdfIn PDF document text
    • http://crabandclaw.com/uploads/files/39839930929.pdfIn PDF document text
    • http://www.asiacoservice.com/file/files/jujemaluvofajorovog.pdfIn PDF document text
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/23o2hjl1qretg9d9tt3ohqsic7/zenor.pdfIn PDF document text
    • https://ddmmaze.altruistictech.org/documents/img/upload/files/savoxunutisiguka.pdfIn PDF document text
    • http://videlec.be/ressource/file/gasorom.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613afad164ce5---mibet.pdfIn PDF document text
    • https://www.lowdoc-loans.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613c6fbaf3717---ruvodebipowikuga.pdfIn PDF document text
    • http://helenhotel.vn/upload/files/8518449866.pdfIn PDF document text
    • http://praguynakorn.com/praguynakorn/picture/datapro/files/24565293738.pdfIn PDF document text
    • http://antansconstructions.com/ckfinder/userfiles/files/lifegi.pdfIn PDF document text
    • https://astoraccessories.com/uploads/ckfinder/files/43696638627.pdfIn PDF document text
    • http://dxqzx.com/ckfinder/userfiles/files/20210918_112301.pdfIn PDF document text
    • http://cancercareresearch.com/userfiles/file/lujipanoris.pdfIn PDF document text
    • https://myclubowners.travelenvogue.com/userfiles/files/vajunaxe.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/rc2htbldjnem17q4229svvni7l/92504563485.pdfIn PDF document text
    • http://labellebeaute.com.hk/ckfinder/userfiles/files/16154867166.pdfIn PDF document text
    • http://interiorsexpress.biz/dayafter/uploadimages/newsimages/file/jiridipamowelupo.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614185e56e42b---rawulozudegex.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/GLLx1DTH0VQ/uplcv?utm_term=delete+call+log+recovery+appPDF 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_off0000e857.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE857 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010069.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10069 17252 bytes
SHA-256: 832dbcc43346709cea2859a90d43b98b90d2c307de849c6d193fcf1a0f298865
font_02_sfnt_off00012d54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D54 10368 bytes
SHA-256: 62ab1fab908d6a056914e6f6fb83790534fe5619e25be7af98643f343e24bc60