Malicious PDF — malware analysis report

Static analysis result for SHA-256 61e90f04bac62d7c…

MALICIOUS

PDF

74.8 KB Created: 2021-09-07 02:51:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8af782e3b6cf047c34f2a42819843523 SHA-1: cb9c7f63421833320ccf2eb34a9a8079cc462188 SHA-256: 61e90f04bac62d7c67756874adea237a21c32f3cd477c3717a29e673800fd2dc
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous external URLs, many of which point to compromised WordPress upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The sample's primary function appears to be redirecting users to potentially malicious content hosted on various domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://hosvagyok.hu/userfiles/file/fodizevuvasokofemaxolipij.pdf In PDF document text
    • http://bmcnx.com/userfiles/file/88415455595.pdfIn PDF document text
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a48fd5c044f---fuzakavan.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160f09dc1b85cb---pokopuzuza.pdfIn PDF document text
    • http://rethabise.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607dd225b9082---38404986201.pdfIn PDF document text
    • https://thejasmineway.net/wp-content/plugins/super-forms/uploads/php/files/ttevs9inrlkih9jmi6udslamcn/11523264256.pdfIn PDF document text
    • http://ifa-astrologie.de/userfiles/file/zugoletulovosapodetorepi.pdfIn PDF document text
    • http://bekkercoon.ru/ckfinder/userfiles/files/rupezewatulinez.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160acfee54be15---mujekotisazijofomef.pdfIn PDF document text
    • http://violetstudio.in/userfiles/file/legafovokijitorule.pdfIn PDF document text
    • http://www.biotanika.pl/upload/file/13308701085.pdfIn PDF document text
    • http://a1-automotivegroup.com/upload/files/pizegenuwuwaxudipimotip.pdfIn PDF document text
    • http://familiehollander.nl/images/uploadedimages/file/9444488354.pdfIn PDF document text
    • https://stagerightstaging.com/wp-content/plugins/super-forms/uploads/php/files/b817c0430973a0f5d943d40d20ee13ef/kidurusadaf.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ff23105cc---zalopomunezo.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/refitumelodofigi.pdfIn PDF document text
    • https://techielingo.com/fck_uploads/files/6687111767.pdfIn PDF document text
    • http://cecev.com/stockages/files/53587104144.pdfIn PDF document text
    • http://goodmix-psc.com/userfiles/files/pifujel.pdfIn PDF document text
    • http://www.oschouston.com/osc/wp-content/plugins/formcraft/file-upload/server/content/files/160bbe6dda5761---83811594858.pdfIn PDF document text
    • https://www.indee-r.fr/wp-content/plugins/super-forms/uploads/php/files/fa07369c5dee35ee8ae8fe572ffc2f09/xitawurunifafotijidiwisul.pdfIn PDF document text
    • http://ellev.fr/upload/files/88184705675.pdfIn PDF document text
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608bb7c2741a4---59979493278.pdfIn PDF document text
    • https://fortlauderdale-carservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cd57606a3a8---25649431439.pdfIn PDF document text
    • https://securitydm.net/slicice/file/sumuvusen.pdfIn PDF document text
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/7ecde667b65586f9e6c762e05bebc65b/xevofibiridotufepusu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=chain+rule+worksheet+with+solutionsPDF 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_off0000bc00.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC00 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d412.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD412 18848 bytes
SHA-256: e5fd6db09b14f139da8d3f115d23cf3af7d2fbbf939fd9dbdeeef390cf37dbb4
font_02_sfnt_off000105a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A2 10516 bytes
SHA-256: 7e2db4c1ed34d94a2cd86499c4e97a3758518129328df243820fc45ed06f032c