Malicious PDF — malware analysis report

Static analysis result for SHA-256 312545d9376f4a5e…

MALICIOUS

PDF

83.1 KB Created: 2021-09-05 08:53:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: f5892249d21e22dbc8e86e291a5c56ca SHA-1: 18917ebc6d67b7155f251841553610cda17d1de0 SHA-256: 312545d9376f4a5e074fa5449da54fbf33f92ca36dbecf0cf9fc31974dadc9cf
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier strongly indicates maliciousness, supported by numerous heuristics identifying the PDF as a link farm pointing to compromised WordPress sites and disposable hosting. The embedded URLs likely serve as lures to external malicious sites, potentially for phishing or to download further payloads. No scripts were extracted from this sample.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 5

  • 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://smidgel.ru/uplcv?utm_term=enhance+your+vocabulary+pdf PDF link annotation
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5ceb190ed---vamifalax.pdfIn PDF document text
    • http://palyavalaszto.hu/teszt/upload/file/foxetiwobibimadejexozisaw.pdfIn PDF document text
    • https://absoluteanytime.com/media_file/files/files/56485267732.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071f2e62ed72---91314855869.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/puxujakitadenidal.pdfIn PDF document text
    • https://ballestermultiservicios.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078a950ac0c1---mozivawakowujokovowamimi.pdfIn PDF document text
    • http://testsitehq.com/ckeditor-ckfinder-integration/uploads/files/16235927469.pdfIn PDF document text
    • http://thehigh86.com/clients/13680/File/65456865756.pdfIn PDF document text
    • http://kup-vino.cz/web/ckfinder/userfiles/files/sibojesigusasokabisu.pdfIn PDF document text
    • http://korean-school.hu/hangul/userfiles/file/denopamafadupu.pdfIn PDF document text
    • http://taxfreepoint.com/file/3915021498.pdfIn PDF document text
    • https://mudateconmigo.cl/wp-content/plugins/super-forms/uploads/php/files/5f8aee0164bd42dc1109872352ffaf76/70961160745.pdfIn PDF document text
    • http://bestorkate.com/uploads/ckeditor/files/78710878060.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/8gkjo3n5os58d6vqliktlbooul/37965173757.pdfIn PDF document text
    • http://klimatyzacjaradom.pl/userfiles/file/98512447254.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/xesejo.pdfIn PDF document text
    • http://www.shipsupply.co.mz/wp-content/plugins/formcraft/file-upload/server/content/files/1608480cc12820---71979016898.pdfIn PDF document text
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160abf157921f1---54403504970.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/1611358ed55414---tibosikogiboxubidazep.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9c9b498df---6439682935.pdfIn PDF document text
    • http://superbarter.sk/media/file/xavisedesaxixojivafa.pdfIn PDF document text
    • http://joelcsimonesq.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/wururemuruvadew.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_off0000e075.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE075 17716 bytes
SHA-256: 68ef1a2a01b45ea1809efb3fd0fb32e31ea9a9de97bd5054db449d50bdb93727
font_01_sfnt_off00010eb9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10EB9 10764 bytes
SHA-256: a9c64e97cc5fd4eca579c8ac81b0a700fd4cbe2693a0cc07246c01e6a14bc6e7
font_02_sfnt_off0001272d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1272D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1