Malicious PDF — malware analysis report

Static analysis result for SHA-256 d998fab871639412…

MALICIOUS

PDF

83.6 KB Created: 2021-09-02 10:27:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: ff28ad607de126272674660ed2aa1f4d SHA-1: 4ee583646279e9174e20f7932a1d591b3b301a88 SHA-256: d998fab87163941296d6f6d9d5e80284e49d3615102758a1eb73db1c64d2e385
156 Risk Score

Malware Insights

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

This PDF file was flagged by ClamAV as a phishing trojan and by an ML classifier with high confidence. It contains numerous external URIs, many of which point to compromised WordPress sites, suggesting it's part of a link farm designed to redirect users to malicious content. The file's structure and the presence of multiple links indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://archism.ru/uplcv?utm_term=mathematical+modelling+textbook+pdf PDF link annotation
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/69708ab66e313319b6b58c10c1b25043/22228435387.pdfIn PDF document text
    • https://ctyhoanongangiang.com/userfiles/file/8277466564.pdfIn PDF document text
    • http://lws-realestate.com/userfiles/files/xotopajuretisugitu.pdfIn PDF document text
    • http://birzebbugastpetersfc.com/files/file/61123666604.pdfIn PDF document text
    • http://www.bestlifepolicy.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b85a519c6b0---10746513384.pdfIn PDF document text
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/30140267750.pdfIn PDF document text
    • http://biosafety.biz/ckfinder/userfiles/files/gerodu.pdfIn PDF document text
    • https://hockeymro.ca/docs/file/69293078512.pdfIn PDF document text
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/6eb1429270abbd9094a810e8165d7487/lipav.pdfIn PDF document text
    • http://gyogytornasziget.hu/uploads/files/74504498832.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/48476233708.pdfIn PDF document text
    • http://mesterek.net/tmp/79322543975.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e941578298b9e2c459729cc281f09d86/xapokowado.pdfIn PDF document text
    • http://unsersohn.com/images/file/vimitizunivubawiwip.pdfIn PDF document text
    • https://maribon.net/app/webroot/files/userfiles/files/46612763692.pdfIn PDF document text
    • https://whitelightdesign.com/wp-content/plugins/super-forms/uploads/php/files/6839162cf33d1d75b6d7415ab55bd96c/20606964206.pdfIn PDF document text
    • http://heorungminhphat.com/luutru/files/jekorewajoxenazagu.pdfIn PDF document text
    • http://christembassydocklands.org/wp-content/plugins/super-forms/uploads/php/files/2c763100ebd44697ddae5fa6a8c96c31/mepaputaxijutivi.pdfIn PDF document text
    • https://saikekanglun.com/filespath/files/20210828101001.pdfIn PDF document text
    • https://trsbarriersdirect.com/wp-content/plugins/super-forms/uploads/php/files/k3sa8dl4pnb4va29lf60jc076r/43224346309.pdfIn PDF document text
    • https://www.booster-p.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a119f38e0ae---95914929979.pdfIn PDF document text
    • https://clove7.com/userfiles/file/jexiju.pdfIn PDF document text
    • http://s8radziejowice-paszkow.pl/userfiles/file/83574661208.pdfIn PDF document text
    • http://songiadabinhphuoc.com/upload/ck/files/nasaxowaj.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_off0000deb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f6c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C2 18168 bytes
SHA-256: be3f4a420700cf20ff105ab70d1fda25126ca9db8eed516dd8aa8640f6d82e55
font_02_sfnt_off0001264a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1264A 11128 bytes
SHA-256: e645f98b3d7c319e7bee1229e69bbeb009896e6eb776147bb41529bf96ffb56a