Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1cf4df0e464a1b4…

MALICIOUS

PDF

70.2 KB Created: 2021-09-23 12:57:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: d85be138b25a01d45fd996e80eea6bc7 SHA-1: 3b46338d81c4ac5687802fd9018605075184589e SHA-256: f1cf4df0e464a1b48907f8bfabc5917e30232f15bb6fd09ea8bda440ed3a13c2
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to various domains, many of which are associated with compromised CMS uploads or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. The presence of multiple external URIs and the 'link farm' heuristics point towards an attempt to direct users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://nomylo.ru/uplcv?utm_term=watch+movies+io PDF link annotation
    • https://sluganarodu.org/userfiles/files/33360564364.pdfIn PDF document text
    • https://profipreklady.cz/www/ckfinder/userfiles/files/viwajup.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/161426507d848e---70399107885.pdfIn PDF document text
    • http://huthamcauquanggiap.com/upload/files/repov.pdfIn PDF document text
    • https://hiperaktivite.info/userfiles/files/99130177185.pdfIn PDF document text
    • http://vxclouds.com/userfiles/file/jebasewapoxefobojibuxor.pdfIn PDF document text
    • http://everest-c.ru/ckfinder/userfiles/files/tixudepebusifoxewus.pdfIn PDF document text
    • http://lemonsport.hu/upload/file/nurutijojanidofoburima.pdfIn PDF document text
    • https://perfecthospitals.com/FCKeditor/file/13834784556.pdfIn PDF document text
    • https://smshealthcareservices.com/ckfinder/userfiles/files/48226471652.pdfIn PDF document text
    • http://contelex.it/userfiles/files/45182215928.pdfIn PDF document text
    • http://safiorida.dk/operatori/userfiles/file/94639968787.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/ae232849c56c9b9202fc8b7921b63fe3/dikupulesedewedek.pdfIn PDF document text
    • http://kronospan-mofa.hu/editor_up/sofakufemodebelelusodot.pdfIn PDF document text
    • http://bluebiz.kr/userData/board/file/vusiwujanovol.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/161418e75d79c4---gozuma.pdfIn PDF document text
    • http://unitekinfostructures.com/userfiles/file/6426520628.pdfIn PDF document text
    • https://kangaroovietuc.vn/webroot/img/files/rukitobafo.pdfIn PDF document text
    • https://lorenzonimmigrationlaw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614924cdc3ba5---sagutus.pdfIn PDF document text
    • http://le-bouquet.be/userfiles/files/binorurezawegedovo.pdfIn PDF document text
    • https://biorenta.lt/ckfinder/userfiles/files/vajunorilufijanimavefivu.pdfIn PDF document text
    • https://vroa.pl/chplusfiles/file/62329968340.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_off0000b2ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2AD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cac4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCAC4 10304 bytes
SHA-256: de803e1ce0e4ec6057cdd9f29cf8d0c7a2906930e89fe813a2aa4b73985063ad
font_02_sfnt_off0000e21b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE21B 16284 bytes
SHA-256: dd41ee69a86c12fc669ca1fd7337916030ca16f4c5f0fa5a16e0726758e6ffd1