Malicious PDF — malware analysis report

Static analysis result for SHA-256 b721f81cef794eb9…

MALICIOUS

PDF

75.8 KB Created: 2021-09-15 11:48:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: fb660f0e21612e50deaa7cfef3bbe532 SHA-1: e99a18fd78b7ac37e132d25dbf2d745b9c84e571 SHA-256: b721f81cef794eb9a4609791047a5378a3a118d59fcdd68764b5dcbd5ebf6296
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. The embedded URLs, such as http://neoclassicalmansions.com/uplds/file/bapojowetupugegakupat.pdf, are likely used to redirect users to malicious sites. Although no scripts were explicitly extracted, the PDF structure and URL patterns suggest an attempt to deliver a malicious payload or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://neoclassicalmansions.com/uplds/file/bapojowetupugegakupat.pdf In PDF document text
    • http://webbyshoe.com/fckeditor/userfiles/file/toxedevigaxomizizesazi.pdfIn PDF document text
    • http://adria-ex.com/images/blog/file/83468656241.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/xatafimofekora.pdfIn PDF document text
    • http://elard-group.com/ckfinder/userfiles/files/80258280294.pdfIn PDF document text
    • http://langeline.com/ckeditor/upload/files/31854386960.pdfIn PDF document text
    • http://trip-sale.ru/userfiles/file/guxonazewovuforubikoz.pdfIn PDF document text
    • http://redactron.com/userfiles/file/37154398622.pdfIn PDF document text
    • http://123dvere.sk/files/file/89139900307.pdfIn PDF document text
    • http://finproekt-msk.ru/userfiles/file/gefuloxozifiwowiloto.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/48f6e5fa9717cd1cad1239512a7f88b4/bifikiwodokedufof.pdfIn PDF document text
    • http://sevimticaret.net/userfiles/file/83287209196.pdfIn PDF document text
    • http://gezond-trakteren.nl/kasteel-doornenburg-img/bestandenfile/23767105004.pdfIn PDF document text
    • https://rtvpuls.com/ckfinder/userfiles/files/nelufexutit.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/gesegaravefuguzivefogubad.pdfIn PDF document text
    • http://aaykpn.com/uploads/editor/files/zulunop.pdfIn PDF document text
    • http://mofrantech.com/userfiles/file/73176132867.pdfIn PDF document text
    • http://tcyy88.com/userfiles/file/2021091021085073499.pdfIn PDF document text
    • https://satbietthu.com/luutru/files/vopomidikemakex.pdfIn PDF document text
    • https://suacuasathcm.com/uploads/files/58833047488.pdfIn PDF document text
    • http://jonkmp.nl/img/cms/file/fujasunonavakidodup.pdfIn PDF document text
    • http://avvocatoandreabruschi.it/userfiles/files/vewifiga.pdfIn PDF document text
    • https://steammining.com/userfiles/file/jukovifefogapupa.pdfIn PDF document text
    • http://autoscuolauniversale.it/userfiles/files/71249466713.pdfIn PDF document text
    • https://verandapattaya.com/userfiles/files/89286962005.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=skyrim+hob%27s+fall+cavePDF 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_off0000c513.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC513 10920 bytes
SHA-256: 7247833a95fff352fda27c79101777d4972191d510bae521fbcaf21d6714ccc1
font_01_sfnt_off0000de72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE72 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f684.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF684 16596 bytes
SHA-256: 87ae93c347a2435f2ef9b6829c4919c3845e32a01977664e99f619f875b600b2