Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8761ae4a983c16e…

MALICIOUS

PDF

75.8 KB Created: 2021-08-14 00:11:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 69f410b47198c821731563c4400b5977 SHA-1: 51c71fd874547811eae1a9cb556328f27c1b02a8 SHA-256: f8761ae4a983c16ede07e4c2ec5524825679db016efb913b820e345666e212ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML and ClamAV as malicious, with heuristics indicating it functions as a link farm. Multiple URLs extracted from the document point to compromised CMS uploads and disposable hosting, suggesting a phishing or SEO manipulation scheme. The document body is heavily obfuscated and unreadable, providing no further context.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/1346dcfcba7bf5acc6267a7266f77593/tebekup.pdf In PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160751be4a0a04---85354602594.pdfIn PDF document text
    • http://www.aqsclimited.com/EditorImages/file/pesomudiramelukidopataj.pdfIn PDF document text
    • http://terredellamagnagrecia.com/userfiles/files/rasusapopop.pdfIn PDF document text
    • http://dabien.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/160c664572114c---litiridefe.pdfIn PDF document text
    • https://betenenergy.com/sites/default/files/file/46497003608.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/56229660064.pdfIn PDF document text
    • http://wittlich-luexem.de/userfiles/file/99101599899.pdfIn PDF document text
    • https://lapalettedesarts.fr/gestion/file/76420146212.pdfIn PDF document text
    • https://psychotherapie-dr-albrecht.de/wp-content/plugins/formcraft/file-upload/server/content/files/16072c1a873bd9---56934276221.pdfIn PDF document text
    • https://www.americansummercamps.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d11ec6348d---buwusenifekegis.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/39665522653.pdfIn PDF document text
    • http://divorcefinance.nl/uploads//file/rufazij.pdfIn PDF document text
    • http://uniroll.pl/user_images/file/rowapomijilorewisujudutuj.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///11082951260.pdfIn PDF document text
    • http://stkvn.ru/wp-content/plugins/super-forms/uploads/php/files/269a1cd9941d8787d9bb0a48188329d9/zunumadelemuxafasixuxemo.pdfIn PDF document text
    • http://morgancountyoh.com/userimages/79801545109.pdfIn PDF document text
    • https://chungcungoaigiao.net/uploads/files/94155618965.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/813772e4c2cea61a903b38c82b8d41dd/11635949882.pdfIn PDF document text
    • https://prana.video/wp-content/plugins/super-forms/uploads/php/files/6vh6452i20frrp6kar6v20736b/80304886044.pdfIn PDF document text
    • http://nprofit.hk/userfiles/jajagetawapizamiwikefa.pdfIn PDF document text
    • http://saothienemb.com/uploads/images/files/4236214031.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/ee03e403fd2509f66169ffb7e8926d21/limaluxes.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=how+to+mount+lowrance+transducer+on+trolling+motorPDF 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_off0000c5b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC5B9 10892 bytes
SHA-256: 6805be9c8adb137d5275b8b23103d070f3d9ad3246dd75885f61de15ca4e3937
font_01_sfnt_off0000deb2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEB2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f6c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6C4 16492 bytes
SHA-256: 163e77c2d383ce93041be170a29cbcf68f208d9c715bbfab760456fe71818c49