Malicious PDF — malware analysis report

Static analysis result for SHA-256 6ad56fed7fdbdb50…

MALICIOUS

PDF

81.9 KB Created: 2021-09-03 14:36:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: c3157f6f1f6c886bd9982322aacd46d1 SHA-1: f01a414924dcedaa4f032d19497d5a9185076def SHA-256: 6ad56fed7fdbdb50c1513057352baa8f6b3f4cd83b5c847c3a0b7304f4dd105a
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to compromised WordPress sites, suggesting an attempt to redirect users to malicious content. While no scripts were directly extracted, the nature of the link farm and the detection suggests it may exploit PDF vulnerabilities or deliver malicious content via embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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 http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609cd18600281---99853465044.pdf In PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160944be44cdef---dadepifigewisupe.pdfIn PDF document text
    • https://telenovella-bg.com/files/mivasevarituzivej.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bb810ae9d4e---6049308978.pdfIn PDF document text
    • https://southtours.com/wp-content/plugins/super-forms/uploads/php/files/910e5kj27g1am84jk7emn3kjg0/tizewibivuganegamopumeg.pdfIn PDF document text
    • https://linkevicius.com/upload/galery/file/62446816824.pdfIn PDF document text
    • http://ahlhy.com/uploads/file/250554461459.pdfIn PDF document text
    • https://ilc.ua/wp-content/plugins/super-forms/uploads/php/files/fig77ua3b5i34mq7fn99bsc8t2/jukagekibakaju.pdfIn PDF document text
    • https://carrieres-pierre.com/userfiles/file/79088707425.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/70915136584.pdfIn PDF document text
    • http://ip-golubev.ru/ckfinder/userfiles/files/38389920610.pdfIn PDF document text
    • https://snoman.mb.ca/ckfinder/userfiles/files/89473029485.pdfIn PDF document text
    • https://namkhoasaigon.vn/web/images/files/lamekarejurekitotiparovu.pdfIn PDF document text
    • https://master.plus/wp-content/plugins/super-forms/uploads/php/files/0a75bec1bad493a4b7e043d9e36289ed/74889737578.pdfIn PDF document text
    • http://mini-garden.ru/userfiles/file/supaguvukenubux.pdfIn PDF document text
    • http://aelma.com/sites/default/userfiles/file/14465778582.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d2e2669cacc---tinimorenor.pdfIn PDF document text
    • https://diphong.com/uploads/bupajelojolugopo.pdfIn PDF document text
    • https://rumputhijau.com/contents//files/52399306478.pdfIn PDF document text
    • http://objetivovender.com/wp-content/plugins/formcraft/file-upload/server/content/files/1610c13ebee18c---38713664252.pdfIn PDF document text
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16112a55146e59---4848944046.pdfIn PDF document text
    • http://seventyfirstclassof69.com/clients/60772/File/jaxakelevubexur.pdfIn PDF document text
    • http://jogamiskolc.hu/ckfinder/userfiles/files/99771624889.pdfIn PDF document text
    • http://randoquad72.fr/userfiles/file/forofejaposakafogufi.pdfIn PDF document text
    • https://www.lashharmony.co.uk/wp-content/plugins/super-forms/uploads/php/files/a0pbf8c0mbpgajg9v7dvi61ofh/74445901957.pdfIn PDF document text
    • http://infinity-pro.ru/userfiles/file/rifop.pdfIn PDF document text
    • http://asztromiskolc.hu/ckfinder/userfiles/files/xejifekupu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=tracing+names+worksheets+for+kindergartenPDF 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_off0000dbf7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBF7 11016 bytes
SHA-256: 6aa97f908d0625bcde705bf3d310762bc8910c4ef1851af2b0dad5f03c255de4
font_01_sfnt_off0000f547.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF547 17228 bytes
SHA-256: f9409624b7f5f304fe0810045a65d6f29a4ef72b4df71ee748a30d43193a7237
font_02_sfnt_off000121c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1