Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d733579df13dc8b…

MALICIOUS

PDF

81.3 KB Created: 2021-08-06 19:22:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5fd0936391ca1a50a5bb89dab264abba SHA-1: 636f9b55be13fb3ee70000b1d9faca4c73a4dce6 SHA-256: 4d733579df13dc8b5b96384a6a7481734ee4e77ec8f9d339975dfcea04c0d4b3
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm with numerous URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure suggests a lure to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://infrive.ru/uplcv?utm_term=snake+vs+block+skins PDF link annotation
    • http://akinmedikal.com/uploads/file/losiduma.pdfIn PDF document text
    • https://wentworthre.com/wp-content/plugins/super-forms/uploads/php/files/34079c736a3e4cc69e97c52a1a31328d/2300057449.pdfIn PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/eeb8d0d5fb9d42ceaa6e2e5583014491/81614901865.pdfIn PDF document text
    • https://pakistanchristiancongress.org/userfiles/file/tagibej.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/21c0ce53e48edc8fff6939b064c0559c/1080280102.pdfIn PDF document text
    • https://hotelritariccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/160bad3f448609---jerarosawotapox.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/8f42750676e8dfe10cb540b3025decf9/losupe.pdfIn PDF document text
    • https://www.couleurs-et-jardin.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16074a8c15059e---pufelurozomubudazezowiru.pdfIn PDF document text
    • http://getawaynewzealand.co.nz/wp-content/plugins/formcraft/file-upload/server/content/files/160c226581a966---53011036571.pdfIn PDF document text
    • https://www.bluegreenshouseboats.in/wp-content/plugins/formcraft/file-upload/server/content/files/1609b3c33af198---84511831777.pdfIn PDF document text
    • https://www.aironface.com/wp-content/plugins/super-forms/uploads/php/files/e3be77e4a44641c527572b60cb0f6ef0/29197995373.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/90a8102ec281ae668886d593c4ad6520/91899874323.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607a00d3f08fb---motifumogikekudurax.pdfIn PDF document text
    • http://monticellotownship.org/userfiles/file/46071163042.pdfIn PDF document text
    • http://cosmoscm.com/contents//files/65246233874.pdfIn PDF document text
    • http://tavernadelsnoguers.com/wp-content/plugins/super-forms/uploads/php/files/58d6f3aa4ffc80507ab894dc86f98244/jutiguxutaxufef.pdfIn PDF document text
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a873d3d8925---wobugizatonewutubaru.pdfIn PDF document text
    • https://www.dentaltaxpros.com/wp-content/plugins/super-forms/uploads/php/files/a16973d6bc3f5d3350bf837d41ec3d54/kuvumobir.pdfIn PDF document text
    • https://www.erenang.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608266e5d465f---79371453399.pdfIn PDF document text
    • http://ypdtools.com/ckfinder/images_store/files/52905976364.pdfIn PDF document text
    • https://antoinepanau.com/wp-content/plugins/super-forms/uploads/php/files/015a1ef94dd51735ef4ab626c755b072/tanubazojum.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_off0000dc74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC74 16888 bytes
SHA-256: af4c016e41e0f2f93838d79d3c321ed0e678b5b602cc44455a9c9f76d9767ac4
font_01_sfnt_off0001084d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1084D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12064 10400 bytes
SHA-256: fd86558ca0803926f88bac5a27fc5c0dbe576e74ae5a899d9e8212c921fc1303