Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fa835d19440b37e…

MALICIOUS

PDF

73.4 KB Created: 2021-03-14 12:00:11 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-20
MD5: 06668bb9e1ad5ecd1108116198103e64 SHA-1: 9a9dbc701b695040c379794b2129e74404ea5c24 SHA-256: 4fa835d19440b37e1edfe9f61e47dda033018abb887ab7956e5e56ad2ca803e4
186 Risk Score

Malware Insights

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

The PDF file contains numerous external links, many hosted on disposable domains, indicative of a link farm used for phishing or distributing further malicious content. Heuristics like 'PDF_SEO_LINK_FARM' and 'PDF_SEO_DISPOSABLE_LINK_FARM' strongly suggest this malicious intent. The ClamAV detection and ML classifier further confirm its malicious nature, likely as a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

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
  • 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.
  • 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/award?keyword=capacity+assessment+form+pdf PDF link annotation
    • https://cdn.sqhk.co/vafegijateno/iek0yjf/92049878778.pdfIn PDF document text
    • https://sijetuso.weebly.com/uploads/1/3/4/4/134499475/8677212.pdfIn PDF document text
    • https://rumitubo.weebly.com/uploads/1/3/4/5/134525427/908799.pdfIn PDF document text
    • http://rixadixiji.scienceontheweb.net/occupational_english_test_for_doctors.pdfIn PDF document text
    • http://reduslim-sito.site/how_to_reset_jlab_true_wireless_earbudsgkvuc.pdfIn PDF document text
    • http://tekupugu.sportsontheweb.net/38005686084.pdfIn PDF document text
    • https://fowuwulavo.weebly.com/uploads/1/3/4/7/134754099/6456808.pdfIn PDF document text
    • https://kafuribawixunav.weebly.com/uploads/1/3/4/8/134897544/momanasojapovewipi.pdfIn PDF document text
    • http://kebenoda.scienceontheweb.net/pifefuwikugun.pdfIn PDF document text
    • http://sexesex.site/brighton_beach_memoirs_play_scriptzzde6.pdfIn PDF document text
    • http://rapoxarawiwalo.sportsontheweb.net/totaxuvalidigapezofiji.pdfIn PDF document text
    • https://cdn.sqhk.co/dejenuluzew/cidVibW/dekivetoti.pdfIn PDF document text
    • https://cdn.sqhk.co/tavikagisato/klCifgi/voice_lessons_near_me_for_adults.pdfIn PDF document text
    • https://cdn.sqhk.co/nokotadi/hhKhajb/malawi_cichlids_care_sheet.pdfIn PDF document text
    • https://cdn.sqhk.co/gobuwovuv/LeEYgg4/11746212181.pdfIn PDF document text
    • https://sutopudebesi.weebly.com/uploads/1/3/1/4/131438093/8274938.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://cd29ef07-728f-4a0b-b57b-23e770395c36.filesusr.com/ugd/f14cf6_75ff8d5cca474f688b9957b014bce72e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d6a34116-c5ce-49ce-9bbb-eb7994cba79a/real_book_6th_edition_contents.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8e3ffd6c-38f5-4237-b75a-636dbc3d76b1/levan.pdfIn PDF document text
    • https://3bdad275-8828-414d-9063-9532e035d791.filesusr.com/ugd/c67d0c_d5ea02522e444da08a0b2698bb1439d3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b218116d-18a0-436b-a425-6eb91dd5f588/how_to_pair_bluetooth_plantronics_voyager_legend.pdfIn PDF document text
    • http://kimawawasero.onlinewebshop.net/xafasenasakimejojawufu.pdfIn PDF document text
    • https://be934b08-0dcc-4e2e-8de1-c3c1c32dbfab.filesusr.com/ugd/d5415a_1c51600b47054e488c3a4f5186525fce.pdf?index=trueIn PDF document text
    • https://b1b0174c-961c-4936-87f6-765e1132391e.filesusr.com/ugd/6cf804_f65485b18ba645eaabe4bb1383fb8e3d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/b6a7c441-951c-43af-9b44-c02505f9c19a/misigupiputix.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d444.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD444 5180 bytes
SHA-256: 74b274d0e7bd0bcb27a0ea7a340986d98ae806b349d231fb25ba29d5f5971e53
font_01_sfnt_off0000e5d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5D4 10096 bytes
SHA-256: fd576f25b2075b6472a62abce65e99c585cc5b8c350cc2ae6df0a7e937698872
font_02_sfnt_off0001086f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1086F 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f