Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6838ec4c886485e…

MALICIOUS

PDF

86.7 KB Created: 2021-07-07 08:52:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 97011935884f5cc55aa675b58e205a07 SHA-1: 1dde99f09e5c18b06795063cb98158a456bcb031 SHA-256: b6838ec4c886485e1f39f1a124f0c11aebb14a0930c26c24577c19294f0ccf30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. While no scripts were explicitly extracted, the PDF structure and embedded URLs suggest it is designed to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/figolutazupexudosogivirub.pdf In PDF document text
    • https://messianic.live/wp-content/plugins/super-forms/uploads/php/files/d3357f2efbba096c226f93ff9e45f4ed/4107596540.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be7bb9de5ec---runazazufe.pdfIn PDF document text
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/4b4f7487add6852f642c8454514131a2/50035022903.pdfIn PDF document text
    • http://nadiadsa.org/userfiles/file/tedopiwekanewewerazokaw.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/vimedoze.pdfIn PDF document text
    • http://multiseal.com.ph/wp-content/plugins/formcraft/file-upload/server/content/files/16086d9d737839---bapowezituxavejutegawijup.pdfIn PDF document text
    • http://asupuro.com/user_data/image//file/31581916800.pdfIn PDF document text
    • https://inchiriereelicoptere.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a934443108e---wevoxasolumakemerabazosow.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160716f6fccdbe---takifi.pdfIn PDF document text
    • https://majorsagilekvaros.hu/uploads/file/revinowesilu.pdfIn PDF document text
    • http://dansecyr.ca/pdf/file/jakesubada.pdfIn PDF document text
    • http://faxik.online/ckfinder/userfiles/files/miditiwidijim.pdfIn PDF document text
    • https://mingyi-lock.com/data/file/userfiles/files/vupisemigajo.pdfIn PDF document text
    • https://evocative.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608a1eedde803---51995214895.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/ddhpdteo2bksbh0g3j57b9kr9j/jusavetuwijakirinodadaz.pdfIn PDF document text
    • http://plenaadoracao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a152607c239---63854687367.pdfIn PDF document text
    • http://erkerlaender.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606f3339234f1---pelulidezopuw.pdfIn PDF document text
    • http://qboardapp.com/wp-content/plugins/super-forms/uploads/php/files/e3d04036921288a3274e26bdf202b584/xeferazixulibejuxaw.pdfIn PDF document text
    • https://szud94.hu/img/sajatfile/files/34840548092.pdfIn PDF document text
    • https://alakharia.com/public_html/userfiles/file/bofukidofil.pdfIn PDF document text
    • https://jennysbooks.com/wp-content/plugins/super-forms/uploads/php/files/4f589839269739131c19c1220e3d3c7c/dakavorobiliba.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b06ddeafa50---lunojowogudurefi.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607798b1b28e2---rowujafajamajabaze.pdfIn PDF document text
    • http://mognational.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ec1f8e2065---nudiwexopogewuxudozoza.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=chicago+manual+of+style+pdf+latest+editionPDF 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_off0000eee1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEE1 11212 bytes
SHA-256: 19a58140a41f82d742025943241fc03d7500e30de8b1cc2389fa3d38188ec49e
font_01_sfnt_off000108d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108D3 17116 bytes
SHA-256: bb8d1223f23283bd7753713e25fde144fd990706cb066d41cb48c1a949a52c9d
font_02_sfnt_off0001354d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1354D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1