Malicious PDF — malware analysis report

Static analysis result for SHA-256 9f856883f9e137cb…

MALICIOUS

PDF

69.8 KB Created: 2021-10-02 18:16:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-02
MD5: cb16973bcbed3afc34c0a053b9c3d032 SHA-1: 946fb8ed34eb1c47e95c9cb2d2f9564a714850d9 SHA-256: 9f856883f9e137cb1081edb68d5a12b9e00061c65b6895f8509145cd9b09ca2c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm. Multiple heuristics indicate the PDF contains numerous external URIs and links to potentially compromised or disposable hosting sites. The embedded URLs suggest an attempt to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://catamma.ru/uplcv?utm_term=another+word+for+superimposed PDF link annotation
    • http://oreoltour.ru/sites/default/files/file/tadozumavite.pdfIn PDF document text
    • http://abovomedia.hu/_user/file/bexuxavosanorogimizatej.pdfIn PDF document text
    • https://eric-parnes.shortex.com/ckfinder/userfiles/files/funeninirajopefisivixewex.pdfIn PDF document text
    • https://posh.hr/files/70037305366.pdfIn PDF document text
    • http://abpaluso.com/upload/file/84352661737.pdfIn PDF document text
    • https://partroyfuneralhome.com/partroy/assets/file/zoniwotexo.pdfIn PDF document text
    • https://uangraja.com/contents/files/kadefapevitipifom.pdfIn PDF document text
    • https://louvre.lv/res/wysiwyg/file/41284547419.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614112244f100---38766921373.pdfIn PDF document text
    • http://dlastudenta.org/Upload/file/zowumasin.pdfIn PDF document text
    • http://pavcargo.ru/wp-content/plugins/super-forms/uploads/php/files/00d16ae0ac1da9b89b3c8d0a76e1bd34/zuwepigubaderubugofal.pdfIn PDF document text
    • https://bywuf.org/upload/editor/files/jebuzuzawave.pdfIn PDF document text
    • http://mybyblos.com/userfiles/file/77690393856.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16144228572995---19341270748.pdfIn PDF document text
    • http://studiopedrazzini.eu/userfiles/files/bekeduvebosowujodatetelaf.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/16136b7ce1a6b2---33515842551.pdfIn PDF document text
    • https://europartner2.pl/uploads/52039547347.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/29465400568.pdfIn PDF document text
    • http://rallyteamwalraven.nl/file/74868619959.pdfIn PDF document text
    • https://palezieux.com/ckfinder/userfiles/files/basimosasaruneluxutitewu.pdfIn PDF document text
    • http://www.cenlafilm.com/siteuploads/editorimg/file/fajusubifutomoje.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1614fd503e9508---xupavewolasigumufaga.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_off0000b00c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB00C 10720 bytes
SHA-256: 10639537d3462eaffa897a27f783102cad1b7cc2958e8be0fd8238808fcf7247
font_01_sfnt_off0000c889.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC889 16080 bytes
SHA-256: 035af0c4bf49f2c361be8d4b5eb7b656c913f1cd6dc70216cfdf9f86901a2fe5
font_02_sfnt_off0000f12d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF12D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1