Malicious PDF — malware analysis report

Static analysis result for SHA-256 bec5373bb0d7d965…

MALICIOUS

PDF

111.7 KB Created: 2021-03-23 00:19:32 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 4925c00e663befc2a97fba8ab62760b5 SHA-1: 11553a66dae68fe989f28d4bebf40396ded43231 SHA-256: bec5373bb0d7d96532178323ab3922618f6c815658aa79d104463518776be304
226 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious File T1059.007 JavaScript

This PDF document was flagged as malicious by ClamAV and an ML classifier. It uses a remote-support lure. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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 contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://golowaki.ru/award?keyword=antarctic+peninsula+map+pdf PDF link annotation
    • http://duwelizub.mywebcommunity.org/madopuxabitugiluliso.pdfIn PDF document text
    • https://kofivenemiwelew.weebly.com/uploads/1/3/1/3/131380814/nigexiranudi.pdfIn PDF document text
    • http://sewukagazub.mypressonline.com/42287577579.pdfIn PDF document text
    • https://cdn.sqhk.co/besudamuge/lMhcbNv/pockets_billiards_and_brew.pdfIn PDF document text
    • https://cdn.sqhk.co/vasibejovej/xKshi2V/neha_kakkar_song_downloadming_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/susopavazane/DijUKHi/64441286407.pdfIn PDF document text
    • https://dapalijika.weebly.com/uploads/1/3/0/7/130738969/f66e4.pdfIn PDF document text
    • https://cdn.sqhk.co/jikowuzu/gjalb9f/kart_mania_one_tap_kart_racers.pdfIn PDF document text
    • https://cdn.sqhk.co/fefowofuk/eHjfIQc/tipelo.pdfIn PDF document text
    • https://gopabaxofusa.weebly.com/uploads/1/3/5/3/135300850/desus.pdfIn PDF document text
    • https://cdn.sqhk.co/rotonoba/0VWjaTP/sanawubodik.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://438e95ed-c264-4db5-88d3-1a9ca8b91b86.filesusr.com/ugd/733c1f_eb499882ad8f48faa53290827ac74578.pdf?index=trueIn PDF document text
    • http://nejesezape.myartsonline.com/zowisofuxipivu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d5523d93-e61b-4c88-b6af-5a2b1de001f8/las_batallas_en_el_desierto_en_ingles.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/df7c179f-1a6c-498e-99ee-92d67218803b/how_to_write_a_congressional_letter.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/49e2489b-bc28-4c8b-9db6-b99acd616490/is_there_a_regions_bank_open_on_saturday.pdfIn PDF document text
    • https://8dfdba76-182f-4dc4-9dda-37a8c8d09dc9.filesusr.com/ugd/4ae4db_da417758a92d4746bcefcad141699822.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b945f64f-9fda-49cc-b5cc-cea1405070ea/free_online_english_grammar_book.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_off000173f0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x173F0 5288 bytes
SHA-256: 929778b58669a22e3bc8d736cfe96e0194eb7255d0450636cc908e8ace1edf56
font_01_sfnt_off000185d5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x185D5 14512 bytes
SHA-256: 264cf76584cf8c381a0da8ef9c609a6318ae85fbb88a54acbeb26b9f784373b5