Malicious PDF — malware analysis report

Static analysis result for SHA-256 90efca0bc3098705…

MALICIOUS

PDF

68.9 KB Created: 2021-09-29 08:59:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 98003faf55c8165e8a15b99e35fe53f3 SHA-1: 1a972978f821cc5d1eb613cb4dc1d1821a692749 SHA-256: 90efca0bc3098705cfbff7c4b61bfd434884aacef977c5bc3a55d6b5aa8202c5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to websites hosted on compromised CMS platforms or utilize disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest the document is designed to act as a link farm, potentially leading users to malicious content or phishing sites. No scripts were extracted, limiting the analysis of direct execution capabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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 http://servicedental.it/userfiles/files/10339023096.pdf In PDF document text
    • http://blgjad.com/upload/files/32981032303.pdfIn PDF document text
    • http://blankheich.de/images/uploads/file/vuvidemonezegidafu.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/1614c037d57b16---bikunirox.pdfIn PDF document text
    • https://www.sherpachristain.org.np/ckfinder/userfiles/files/jodenanivufopiwenodijuwu.pdfIn PDF document text
    • http://itcbeautytrainingschool.com/userfiles/file/26027199444.pdfIn PDF document text
    • http://vhz.cz/user-files/wujewuko.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/161481b0e8c1cc---wuxisedupebike.pdfIn PDF document text
    • https://florissantdesign.nl/docs/Image/file/miwokulajomedi.pdfIn PDF document text
    • http://polins.org/public/userfiles/file/gopiviviva.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/58385840084.pdfIn PDF document text
    • https://miltonmattox.com/userfiles/file/zekoxakubonib.pdfIn PDF document text
    • https://menokatea.com/ckfinder/userfiles/files/71402161619.pdfIn PDF document text
    • http://rexant.by/upload/editor/files/fodovesorizagivofeje.pdfIn PDF document text
    • http://ebrinteractive.com/userfiles/file/kogated.pdfIn PDF document text
    • http://rudolphi.nu/userfiles/file/56644609831.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f96afc72a2---43949308604.pdfIn PDF document text
    • http://www.rsvpcatering-ar.com/files/imagesfile/kiloju.pdfIn PDF document text
    • http://xz-brand.com/ckfinder/userfiles/files/89181023335.pdfIn PDF document text
    • https://fzclicks.com/demo/files/editor/file/tedunudipavewi.pdfIn PDF document text
    • https://www.prshots.com/ckfinder/userfiles/files/18831183822.pdfIn PDF document text
    • http://pcccmiennam.com/media/ftp/file/7385895168.pdfIn PDF document text
    • http://onroerendgoedindex.nl/images/uploads/kalegumiforubisagilot.pdfIn PDF document text
    • https://newoptic.sas-global.mn/uploads/files/36246531501.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=clannad+game+download+androidPDF 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_off0000af02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF02 15084 bytes
SHA-256: 4aa5b7154c15c546ef2a545fa2a8f97289ca50e12c2210511b5a86ac45d01522
font_01_sfnt_off0000d533.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD533 10444 bytes
SHA-256: deb7e27af4b5b8490ae1954ef343e3fe453f762e9539efe7e29dfdf2a8e72a86
font_02_sfnt_off0000eca2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECA2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1