Malicious PDF — malware analysis report

Static analysis result for SHA-256 09a3386cdbe76913…

MALICIOUS

PDF

90.8 KB Created: 2021-10-10 19:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 51328a373c8c9ca5a9c6d69fb29cd04c SHA-1: 5de328a0f0dd673c39c48fff3155a93f7c35e0ad SHA-256: 09a3386cdbe76913b9394e502605a9b41f2dbb7c3c1d673d110f69ed96b44a1c
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple PDF-specific heuristics related to link farms and compromised CMS uploads further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9971

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://perfecthospital.net/FCKeditor/file/88151952379.pdf In PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613bf3463788e---pusekawopajumefo.pdfIn PDF document text
    • https://demo.wsbe17hongkong.hk/_bin/ckfinder/userfiles/files/39483938011.pdfIn PDF document text
    • https://festivalecolo.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613624e7ace3a---21404752708.pdfIn PDF document text
    • http://klusjesindex.nl/images/uploads/mexazowiwesikarino.pdfIn PDF document text
    • http://alhambra.kopanramen.com/uploads/files/sibovedanani.pdfIn PDF document text
    • https://seedomoretravel.com/files/files/gepubofugijutisamesuloji.pdfIn PDF document text
    • http://www.vljainandco.com/userfiles/files/50302144563.pdfIn PDF document text
    • http://hydrogears.com/survey/userfiles/files/25911037391.pdfIn PDF document text
    • https://lanna-flyingclub.com/ckfinder/userfiles/files/52257758170.pdfIn PDF document text
    • http://xmzhj.com/UserFiles/file/47166761009.pdfIn PDF document text
    • http://georgewongdesign.com/gwd/upload/files/muwomoza.pdfIn PDF document text
    • http://wsospice.org/uploads/userfiles/file/file/zoxaxul.pdfIn PDF document text
    • http://galsabino.it/userfiles/files/88550050110.pdfIn PDF document text
    • http://methese.com/upload/files/fimufobuxifijev.pdfIn PDF document text
    • http://abwnickersonplaza.com/uploads/files/80022170953.pdfIn PDF document text
    • https://5uempat.com/contents/files/17738061392.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/givokodobamab.pdfIn PDF document text
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16155a2bf0c499---35741781148.pdfIn PDF document text
    • https://loyallcanada.ca/editor_files/file/43184752191.pdfIn PDF document text
    • http://abwferrellpkwy.com/uploads/files/namigojefid.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/51615043505.pdfIn PDF document text
    • http://auto4-spb.ru/public/images/ckfinder/files/wikixamejigejawe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=advocate+good+shepherd+central+schedulingPDF 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_off0000f7d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7D0 10940 bytes
SHA-256: a88d20de361e8e34d3a784a4d2cd8170cbfb059228daab2ea5f94dc94fa89c4f
font_01_sfnt_off000110eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x110EB 20328 bytes
SHA-256: 55229ef200eb794698549b5b2d0068ae8d8bc893217a2903ccfe3ffe27e6f25f
font_02_sfnt_off00014576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14576 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1