Malicious PDF — malware analysis report

Static analysis result for SHA-256 c896bbc082a21921…

MALICIOUS

PDF

76.0 KB Created: 2021-09-01 13:58:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 93b4cda85a04e9f0e1ca7ff13a7ff6a2 SHA-1: e320fabb5c564cebaa35afaec1ef6a80631c0133 SHA-256: c896bbc082a21921bde3ffddb91e061581646bb436beed99a9ad5315f254bc76
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing an embedded JavaScript stream and a significant number of external URIs, many of which point to compromised or disposable hosting. The PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics indicate a deliberate attempt to create a link farm for SEO manipulation or to host malicious content. The embedded JavaScript, though not fully analyzed, is a common vector for further exploitation in PDFs. The ClamAV detection further supports its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://cfi-registration.org/buzzboxgift/img/userfiles/files/lizuf.pdf In PDF document text
    • https://ikitellirezistans.com/upload/files/86826305994.pdfIn PDF document text
    • http://maduraigarlandshop.com/userfiles/file/jutefetakatoledetonefenif.pdfIn PDF document text
    • http://ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/vuviwazolobuvusunufadopik.pdfIn PDF document text
    • http://english-island.pl/wp-content/plugins/super-forms/uploads/php/files/51m0eln7turctc6as6ojc88f53/sawaketaxa.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/mufarepu.pdfIn PDF document text
    • http://pc75.net/upfiles/file/1624917986.pdfIn PDF document text
    • https://www.acptechnologies.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b98c273840---56614909842.pdfIn PDF document text
    • https://callmarkinvestments.fortunekenya.com/callmark/files/gozetuw.pdfIn PDF document text
    • http://clinicaveterinariailmarzocco.it/userfiles/files/6364903779.pdfIn PDF document text
    • http://kfnmdg.com/upfolder/e/files/20210602201754.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16072d878aa3a8---71884014593.pdfIn PDF document text
    • http://solyaris.pro/admin/ckfinder/userfiles/files/27920043877.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a79059853b2---20728947145.pdfIn PDF document text
    • http://fiumevivo.it/userfiles/files/dipixud.pdfIn PDF document text
    • https://blnk.eu/userfiles/files/23485614994.pdfIn PDF document text
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ab35a453dd6---57867439045.pdfIn PDF document text
    • http://lngpetro.com/userfiles/file/21991534171.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/0a79db8f344bb95a44a0f68b68d490f0/42588855738.pdfIn PDF document text
    • https://www.reparaciondebomba.com.ar/wp-content/plugins/super-forms/uploads/php/files/9onle47mmeppqigujcclbt0hm1/gefonizupafosilileme.pdfIn PDF document text
    • https://aeternoplanning.com/ckfinder/userfiles/files/bedobokeb.pdfIn PDF document text
    • http://tecnoservizi.com/userfiles/files/zuvoritex.pdfIn PDF document text
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/e29089995b82ca05159a8119a80460f6/3401521228.pdfIn PDF document text
    • https://hansenlight.com/UploadFile/files/74856196875.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/31a5565f885b0049af073b8785cff02b/zefafawidugad.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/ngfLrbzwjls/uplcv?utm_term=why+is+it+necessary+for+gametes+to+be+haploidPDF 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_off0000c72a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC72A 11312 bytes
SHA-256: 91913b679232568a12869eb889b6a9eae9f91435062251f4ec5f8ee2501decbd
font_01_sfnt_off0000e12a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE12A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f93c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF93C 15660 bytes
SHA-256: a59a405307e9d175c0ff888e7e8f771d1440cd67a77b463e368865371ba5488e