Malicious PDF — malware analysis report

Static analysis result for SHA-256 f334a88a382bfcb8…

MALICIOUS

PDF

79.9 KB Created: 2021-09-04 09:01:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 2e1c22f77664ab4b6916e7c3955fc0c6 SHA-1: cce62a976e0dccc8a61ff724e74cb4bf647aea4c SHA-256: f334a88a382bfcb8a270a108f7c69f3fd592c67a698a39161909ec25e84ce1e9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links pointing to compromised CMS upload directories, indicating a link farm designed to distribute further malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically phishing or trojan delivery. Although no scripts were directly extracted, the PDF structure and URL patterns are consistent with malicious document lures.

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://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/1608ded7349445---sopegeva.pdf In PDF document text
    • http://marthomaiticherukole.com/userfiles/file/wisobosifibidajese.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/c1d02398a4582354562bfc773f4cba28/53283299823.pdfIn PDF document text
    • http://goteneplast.se/files/images/file/33756167814.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6a3d22c391---67975434375.pdfIn PDF document text
    • http://soon-xin.com/fckupload/file/litiweririk.pdfIn PDF document text
    • http://baigeleather.com/userfiles/file/kurimerunero.pdfIn PDF document text
    • https://paklya.su/design/img/upload/file/78271647843.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abb0320a572---59449292585.pdfIn PDF document text
    • http://magnachip.cn/userfiles/file/20210509091820.pdfIn PDF document text
    • http://drapikowski.pl/uploaded/fck_files/file/3992675412.pdfIn PDF document text
    • http://yourtruck.be/upload/ckeditor/file/posenixiganekofururajupu.pdfIn PDF document text
    • https://www.hontoys.com.au/wp-content/plugins/super-forms/uploads/php/files/m0ngfqgoh9pu289kapeonff86i/nesixebarevulivonebi.pdfIn PDF document text
    • http://amphorabeautyclub.com/campannas/file/tororurama.pdfIn PDF document text
    • http://wamer.org/userfiles/file/21041391921.pdfIn PDF document text
    • http://novosib-sport.ru/ckfinder/userfiles/files/nidodolijumo.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/23606cbc1bd415a870806f1722eed1a9/22245704859.pdfIn PDF document text
    • https://bikidi.com/UpFiles/WebEditorFiles/file/rawarubanimomekariwij.pdfIn PDF document text
    • http://chnli.tw/CKEdit/upload/files/16324817539.pdfIn PDF document text
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160720abf5748a---14475946967.pdfIn PDF document text
    • https://citronixdeflection.com/nbloom/fckuploads/file/40893662665.pdfIn PDF document text
    • http://fullcolorspandoeken.nl/userfiles/file/gejudiba.pdfIn PDF document text
    • https://miet.hu/kepek/baradovonubupu.pdfIn PDF document text
    • http://lagostena.it/userfiles/files/29313364717.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=turgeon+immunology+and+serology+pdf+free+downloadPDF 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_off0000d125.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD125 11004 bytes
SHA-256: f302a684d08f9d0e98e7707012f0e252e5bbc3f745888f4ebe3fb85a48e0d274
font_01_sfnt_off0000ea88.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA88 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001029a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1029A 18204 bytes
SHA-256: 205420a5bed15fdb92adfcbaeb55a19047d7143ccdd1882ca17d3ba7f3a7b71b