Malicious PDF — malware analysis report

Static analysis result for SHA-256 d09f8ff58bd33a26…

MALICIOUS

PDF

79.5 KB Created: 2021-09-07 12:19:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: fc1f999c026de1f04465a1d55216c96f SHA-1: 274b28b131f09218fe5103bf6333ba8d9204b714 SHA-256: d09f8ff58bd33a26b95442bae0a4912f18042dcf49095ee39e31a77bc35d3472
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress sites or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the nature of the URLs and the heuristic firings point towards a malicious document designed to exploit user trust.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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=append+pdf+files+adobe+reader PDF link annotation
    • https://ukmriptek.org/codeIgniter-hmvc/userfiles/files/motobitusoras.pdfIn PDF document text
    • http://dogalakustik.com/depo/sayfaresim/file/netaravisavunitiwibavid.pdfIn PDF document text
    • http://domplus.su/userfiles/files/94956027923.pdfIn PDF document text
    • http://vibrosystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a3d11ccc80e---jevekusato.pdfIn PDF document text
    • http://gaskinfamilyreunion.com/clients/b/b7/b798c9f9e2af69c3a5b950a06e4ade8e/File/88609152023.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160aff2464a093---32588171481.pdfIn PDF document text
    • https://kisikana.hr/userfiles/file/83770155482.pdfIn PDF document text
    • https://www.hotwaterfactory.com.au/wp-content/plugins/super-forms/uploads/php/files/5eefbec5e47d3d6d3e2b80f73d176690/5198648014.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5c1e80f8b6---60862319263.pdfIn PDF document text
    • https://arenda1s.ru/wp-content/plugins/super-forms/uploads/php/files/fa31504c9ca52454fa895a163c69be3a/2541460733.pdfIn PDF document text
    • http://businessvaluationapp.com/fck_files/file/3900549667.pdfIn PDF document text
    • http://drinkandshrink.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16084532447b45---rozowofav.pdfIn PDF document text
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/160812d698b496---76888512342.pdfIn PDF document text
    • http://bubblesoflove.net/wp-content/plugins/formcraft/file-upload/server/content/files/16099c3ea6ed08---71599113775.pdfIn PDF document text
    • http://www.aportecnica.com/imagenes/editor/file/4091254248.pdfIn PDF document text
    • https://justbuymeds.net/userfiles/file/dagixinigugukaxedud.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/832357cfd03a594ebd12cb8876aff0ed/nemasel.pdfIn PDF document text
    • http://www.optionassurance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16071ffe74ec1a---72399582950.pdfIn PDF document text
    • http://busankid.com/webfiles/board/file///50714644283.pdfIn PDF document text
    • http://timelessmebel.ru/wp-content/plugins/super-forms/uploads/php/files/6f5663035d2da9a43410a201e0b5eda8/jozemimoxezavinogimugaw.pdfIn PDF document text
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080b3ca9ed0a---balelonowogovovatog.pdfIn PDF document text
    • https://sikanderajam.com/Robinson/ckfinder/userfiles/files/86574671939.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_off0000d354.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD354 17536 bytes
SHA-256: cffc42b79fc3895ff3ca5e821c48c732db5b4bcc026427d1f1ea1188a315c66d
font_01_sfnt_off000100ec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100EC 10512 bytes
SHA-256: 3911c345b34f2ae59b53762758f0f67deb3edc4ce08525fc14d42336abe92223
font_02_sfnt_off000118b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1