Malicious PDF — malware analysis report

Static analysis result for SHA-256 fb34f8f76d9c29f2…

MALICIOUS

PDF

83.7 KB Created: 2021-03-24 08:28:55 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-13
MD5: 777980676301a4c2b8e2ddc4069dd7af SHA-1: 8917fc684d1240620658dba2a61b12a07ad13b66 SHA-256: fb34f8f76d9c29f21e5ac6faac39c6e14643e92a78ba3c1b8c7d88e3e92eefb6
126 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains an embedded URI pointing to a suspicious domain, vilenefex.ru, which is likely used for phishing or to serve a second-stage payload. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further suggests the document is part of a link farm designed to obscure malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://vilenefex.ru/strik?utm_term=how+to+be+a+great+team+leader PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4501659/normal_603d3d879ed3c.pdfIn PDF document text
    • http://daliadiago.com/tokojedaviriretuswnkw4.pdfIn PDF document text
    • http://hook-up.fun/bojajezitanozewopffalf.pdfIn PDF document text
    • http://zitokik.iblogger.org/abolition_of_untouchability.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4387232/normal_5fc85cb396977.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4405946/normal_6023fd0a60bca.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4473322/normal_6003898c37b4f.pdfIn PDF document text
    • http://pigaxugopaxazuz.22web.org/agneau_de_dieu_messe_de_la_trinit_partition.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393188/normal_602906209cc36.pdfIn PDF document text
    • http://save50it.info/vox_ac15_handwired_for_sale1nqc8.pdfIn PDF document text
    • http://tekplafond.xyz/lininetizajemasw266.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4486743/normal_5feb055c62ce8.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://7054f9d6-44ea-4b6c-8535-0d04e7cb9957.filesusr.com/ugd/963b03_075f61e7ff6c4c5fb6c658c610c670b6.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/29bd3800-67d3-47af-9152-ad1d6c8ab54f/tik_tok_dance_songs_playlist_2020_clean.pdfIn PDF document text
    • http://jilutuve.rf.gd/70915448085.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/aa25d782-1171-474e-8fc6-ec6ff00f6b2b/80559230625.pdfIn PDF document text
    • https://fa53e508-d88d-41cb-897c-7a5b6f1bfcc3.filesusr.com/ugd/361045_5351022a1464425bb3dadd16ee27f080.pdf?index=trueIn PDF document text
    • https://d8ec88ce-93b1-4b83-b294-7016fd5b5063.filesusr.com/ugd/366252_210cfa9c2c8e4257a0c7f8ec9b09785c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/c9b93871-4f2a-4b96-ad32-69053b8103ca/64852895027.pdfIn PDF document text
    • https://f803bf1b-e1c2-47f6-a41f-c9785c88fbd4.filesusr.com/ugd/bf07b1_1636e8367fab46d8b0be97dcf79f7968.pdf?index=trueIn PDF document text
    • https://679cd94f-bb1f-411a-9684-d99498fe93d6.filesusr.com/ugd/ce16d4_d007ee71c1214a15b6e37af472b09bd4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f1bfadc5-6900-46c9-9bc0-9f9c258e60ec/sinivejov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a168e626-76ed-4f93-8ab9-47e71e1b88e2/ramana_maharshi_books_online_free.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010aa5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA5 5160 bytes
SHA-256: 570252a1ae8639882025cc2327c28a531bd9a65845f0f8e85d4347fc3d9ded3f
font_01_sfnt_off00011c2b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C2B 11024 bytes
SHA-256: c77a604a313e5abd52613c711202b718b6f41d58c18c3b27d2da916242cbf784