Malicious PDF — malware analysis report

Static analysis result for SHA-256 ca6367c210c64a0e…

MALICIOUS

PDF

74.9 KB Created: 2021-09-18 09:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ade9000ffb8d67eb2141acd9399f1b2f SHA-1: 4e663dcb8f9e28068be30402a0372985d3ff00ff SHA-256: ca6367c210c64a0e59ba2ea155696a6499fd6abdca8ecf1203ed33a2d0411dbc
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external PDFs hosted on various domains, many of which are flagged as a link farm on disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. No scripts were extracted, but the presence of multiple external links suggests an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://www.stock2morrow.com/ckfinder/userfiles/files/43948571897.pdf In PDF document text
    • http://clinicaveterinariacittadivignola.com/userfiles/files/16856991680.pdfIn PDF document text
    • http://solo-reisen.com/media/images/file/24858703664.pdfIn PDF document text
    • https://k85shj16h-561lt.com/contents/files/zumobakupitute.pdfIn PDF document text
    • https://thietbivesinhsonhoa.com/webroot/img/files/jawakoxovetinerufagitipa.pdfIn PDF document text
    • http://kiemdinhcan.com/Images_upload/files/dikosumijev.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/17721926811.pdfIn PDF document text
    • http://gajagotour.com/UserFiles/file/42944501534.pdfIn PDF document text
    • http://sunnyten.net/userData/board/file/39334799032.pdfIn PDF document text
    • https://tessuno.com/upload/files/61399916a3a85.pdfIn PDF document text
    • https://slicktechproducts.com/newerac2c/userfiles/file/waxerudowafofixunuxoxurez.pdfIn PDF document text
    • http://archi-m.ru/userfiles/file/13780261545.pdfIn PDF document text
    • http://arcstema.com/userfiles/files/wigujegabudolob.pdfIn PDF document text
    • http://maudchristan.nl/ckfinder/userfiles/files/98308783904.pdfIn PDF document text
    • http://morecoredesign.com/images/imageUps/files/rulut.pdfIn PDF document text
    • https://www.meditech.cz/ckfinder/userfiles/files/lutikuletisolopezupozago.pdfIn PDF document text
    • https://aluminiosarla.com/userfiles_arla/files/56375255965.pdfIn PDF document text
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379f3369e73---batufosikejupano.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/uqk2oq5ds6u4ng7cgolha8uc6j/vuvufe.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=tom+and+jerry+the+spy+questPDF 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_off0000bc84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBC84 10972 bytes
SHA-256: 6b65b7b7ff6203fcb79e14083c098bceecc4b0a63a1eedfb637894b3d16e6f1b
font_01_sfnt_off0000d5a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000edb6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDB6 18032 bytes
SHA-256: 7f94ad1736fc10561f0c1f6f53c852ab35ddb12453ffde4228cdec7a93a2b2c9