Malicious PDF — malware analysis report

Static analysis result for SHA-256 b81cbd825a6a3255…

MALICIOUS

PDF

81.9 KB Created: 2021-04-16 08:04:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: f634c5edaaf7d6366545f3c6c2cb7a5c SHA-1: d5d5ef71f9d27031448ccb264540753477315cd7 SHA-256: b81cbd825a6a3255a3dece7fc2358e2e882fa8c7102c875e19cecafcb8acc0dd
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to disposable domains, indicating a link farm or phishing attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded URIs are consistent with techniques used to redirect users to malicious sites for further exploitation or credential harvesting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://jumiwimov.ru/strik?utm_term=helter+skelter+film+1976+streaming PDF link annotation
    • http://f1l3download.site/black_and_decker_spcm1936_cordless_electric_lawn_mower_36v_battery_chargerg1zv3.pdfIn PDF document text
    • http://hookup671.site/22734601417x1ron.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4485001/normal_601ef241c0a24.pdfIn PDF document text
    • https://bexusisase.weebly.com/uploads/1/3/4/5/134596812/bisewidorega_vunezimenovanot_fadezidu_furatapufa.pdfIn PDF document text
    • http://jobware.pro/sat_practice_test_5_essay_examplef9n8w.pdfIn PDF document text
    • https://dorixakogika.weebly.com/uploads/1/3/6/0/136051108/4eadcef33.pdfIn PDF document text
    • http://rijebipimaba.getenjoyment.net/bsc_math_book.pdfIn PDF document text
    • https://zesuloni.weebly.com/uploads/1/3/4/8/134892945/aff660.pdfIn PDF document text
    • http://vilopeg.xyz/carson_dellosa_spanish_answer_key3vdfj.pdfIn PDF document text
    • http://national-verifyteam.com/free_bill_of_lading_template4j0mm.pdfIn PDF document text
    • http://sizerasadaxer.mywebcommunity.org/76222323607.pdfIn PDF document text
    • http://pristav.pro/agile_transformation_coach_ausbildung4goxp.pdfIn PDF document text
    • https://kemosufasegu.weebly.com/uploads/1/3/4/3/134348140/kolelomo.pdfIn PDF document text
    • http://persequen.com/rival_food_slicer_model_1101e_5zbvi5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4456119/normal_600eb83d7b3c5.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4367951/normal_5ff66433b9227.pdfIn PDF document text
    • http://im-marceting.site/tmnt_portal_power_pc_review0pfbs.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://uploads.strikinglycdn.com/files/45115753-b05f-482a-b883-0dd98261f410/how_did_us_involvement_in_latin_america_affect_the_relationship.pdfIn PDF document text
    • http://butorinowu.myartsonline.com/todukobelelujegagar.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5c324923-2891-4581-bf0a-f780bd8f400a/how_do_you_make_pot_roast_in_a_pressure_cooker.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/288b92fb-680d-4ce8-8c53-e6894c7b6681/que_es_un_genero_literario.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/097b3a3b-b774-4e1b-9130-802099fb5989/how_to_put_a_vinyl_sticker_on_a_car_window.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8039d1fb-109f-46be-bb77-1b73ea715b0c/46182476036.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_off0000f511.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF511 5232 bytes
SHA-256: c67f3fe9f38b65e451728ea1a6f261453597eb71e012c17fac94c4c382a072d8
font_01_sfnt_off000106b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106B8 11012 bytes
SHA-256: 8de40df0fcddf4d836ae857972d8b8dea3e7ca0cffd319d4d5937ecc31d77d30
font_02_sfnt_off00012c3e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C3E 4324 bytes
SHA-256: 9f355172d696dda274cac500966718f112ce76951f19577ac4888987ea6471b2