Malicious PDF — malware analysis report

Static analysis result for SHA-256 5ef428268af400e5…

MALICIOUS

PDF

77.2 KB Created: 2021-09-01 14:21:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 4132433f2676c136eda34d04ff1878f4 SHA-1: 0c99c6e9f36ae50657708d4329bcce898da87008 SHA-256: 5ef428268af400e548a37083d11b8b934293687529a03abd31c1d3b0255b787b
96 Risk Score

Malware Insights

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

The PDF contains a link farm hosted on multiple compromised websites, suggesting an attempt to distribute malicious files. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of using disposable hosting for these links, further reinforcing the malicious intent. The ML classifier also flagged this PDF as malicious with high confidence.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9827

Heuristics 5

  • 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://dataprint.ie/uploads/file/81889345181.pdf In PDF document text
    • http://alexlunacoach.com/img/editor/file/33151342593.pdfIn PDF document text
    • http://www.sphotobooth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f61fe4c8e1---39670346658.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160cbe52624c1a---41132783680.pdfIn PDF document text
    • http://royalgoodviewresort.com/Uploads/file/lebeweweratuxubejosigofiz.pdfIn PDF document text
    • http://www.danvillern.com/wp-content/plugins/super-forms/uploads/php/files/i3laaesck4cc1i6sbg8umaeir5/72215412464.pdfIn PDF document text
    • https://cuisinescartier.ca/upload/editor/file/dusagosapezabaxawopakuvin.pdfIn PDF document text
    • http://kleinschaden.expert/userfiles/file/vazunu.pdfIn PDF document text
    • https://jogamiskolc.hu/ckfinder/userfiles/files/rifosonubapoxobe.pdfIn PDF document text
    • http://tauben-buchmeier.de/kleinberliner-schuetzen/userfiles/files/73970339090.pdfIn PDF document text
    • http://veivel.com/userfiles/file/kojekisoxawitatower.pdfIn PDF document text
    • http://papinchess.ru/userfiles/file/natolakovujokobal.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d620448ba8---26457545552.pdfIn PDF document text
    • http://cleangroupbd.com/ck/upload/files/gikufuvaxumowunis.pdfIn PDF document text
    • http://miskolciharsona.hu/pictures/file/lefoluwivovawerexi.pdfIn PDF document text
    • http://vidol.eu/userfiles/file/nilebapupokumuposepasi.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/dueqdks3qmdgpbf0fb1f5s7pbn/3529392832.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611db79b39fcd---61127484298.pdfIn PDF document text
    • http://sgpeo.pl/users//file/bapezifugomigafoxazu.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16083d55ba0faa---56716492652.pdfIn PDF document text
    • https://mavibusiness.it/file/3861219054.pdfIn PDF document text
    • http://evabody.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606f59342d690---89162862899.pdfIn PDF document text
    • https://salvatoredivilio.it/userfiles/file/5721331395.pdfIn PDF document text
    • http://vucert.vn/uploads/files/18866121338.pdfIn PDF document text
    • https://at1-turbo-j3t.com/contents/files/16151496754.pdfIn PDF document text
    • https://felix-schulze.biz/wp-content/plugins/super-forms/uploads/php/files/d6vhk7q6iqutpbt3k4qsja3ofk/84669853030.pdfIn PDF document text
    • https://tipresentoio.it/images/file/vitureku.pdfIn PDF document text
    • http://cpk.by/ckfinder/userfiles/files/90890822632.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=vacation+approval+formPDF 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_off0000cbeb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBEB 17252 bytes
SHA-256: 4d19935e7c896e730ad3028c4d6b8dbf26758037c27afef2e4b504802f489ef8
font_01_sfnt_off0000f804.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF804 10376 bytes
SHA-256: cc30841ef2edeba01dfd62d3703c5f2daed1e77ad615a189263ff9a66cc53910
font_02_sfnt_off00010f7c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F7C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1