Malicious PDF — malware analysis report

Static analysis result for SHA-256 37d7cd5cde40c349…

MALICIOUS

PDF

74.0 KB Created: 2021-04-13 02:40:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: e1a72868a2a782ce78b8ce4228ea3185 SHA-1: 74fa5360896b8e7008cd7371cc5c90ea7503832d SHA-256: 37d7cd5cde40c349596645e723de8cfb42d24176f32302dd525b3af2bc27131e
186 Risk Score

Malware Insights

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

The PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external links point towards a malicious document designed to redirect users to potentially harmful sites, likely for credential harvesting or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 6

  • 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.
  • 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://bologen.ru/strik?utm_term=probability+distribution+-+pdf+pmf+and+cdf PDF link annotation
    • https://cdn.sqhk.co/valujoper/eVtjdic/zogupip.pdfIn PDF document text
    • https://vaferevipesefur.weebly.com/uploads/1/3/0/9/130969420/1cbe5a.pdfIn PDF document text
    • http://subbellassecret.com/215118231459nh19.pdfIn PDF document text
    • https://cdn.sqhk.co/wubukuxivupe/kOdQgiR/melodyne_free_download.pdfIn PDF document text
    • https://cdn.sqhk.co/tuxikotimux/kBOajja/excuse_letter_format_student.pdfIn PDF document text
    • https://relabibede.weebly.com/uploads/1/3/2/8/132816075/fidobagerev-posafasarexemo-dapidalifomo.pdfIn PDF document text
    • http://shimano-stradic.ru/gokukekamolvi.pdfIn PDF document text
    • https://cdn.sqhk.co/lilaxikixo/idr9jh5/ice_cream_near_me_nyc.pdfIn PDF document text
    • https://cdn.sqhk.co/letarezetap/CKsihKb/40504930244.pdfIn PDF document text
    • http://tryici.xyz/dunkin_donuts_chocolate_frosted_cake_donut_caloriessgl4q.pdfIn PDF document text
    • http://odemebayisitrafik.com/seo_2020_tipszg51b.pdfIn PDF document text
    • https://cdn.sqhk.co/luvuxokam/gBgighT/the_exorcist_imdb_parents_guide.pdfIn PDF document text
    • https://cdn.sqhk.co/gederanew/yjeonO5/jurassic_world_the_game_mod_apk_hack_download.pdfIn PDF document text
    • https://cdn.sqhk.co/riwifesineji/NficmZ1/76988750946.pdfIn PDF document text
    • https://cdn.sqhk.co/rojarimeg/enjigNm/cross_stitch_patterns_christmas_ornaments.pdfIn PDF document text
    • https://pibulibeles.weebly.com/uploads/1/3/5/3/135324177/tufunurafapomolulix.pdfIn PDF document text
    • http://life50it.pro/what_exactly_is_enlightenment21um4.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4a1fbaa0-0e67-401b-a466-96699e2e5642.filesusr.com/ugd/9647bf_40659ebe2e964ed383c7ae01edaca988.pdf?index=trueIn PDF document text
    • https://7fd9f749-07b0-48f8-ad51-68075edef824.filesusr.com/ugd/197648_dea881ae5a2d48ccaab02f30e8dbfe8a.pdf?index=trueIn PDF document text
    • https://8860adff-7f0b-4cf3-a358-cdd560dff136.filesusr.com/ugd/625844_2ec5e629511948e591f670cd98dd7050.pdf?index=trueIn PDF document text
    • https://0e01c86c-6ad9-43de-bc04-b8819f410213.filesusr.com/ugd/73c254_c098fe117a3746c5a37ee15fda0a600d.pdf?index=trueIn PDF document text
    • https://37523d11-79cf-4eb3-ada4-f05de57c71ee.filesusr.com/ugd/275374_e86360cc4d7846f8bf2a5650344ff912.pdf?index=trueIn PDF document text
    • https://74a5c9af-61bb-4d76-9351-4d02c0bf652a.filesusr.com/ugd/e33828_a236dc4edfb3483486fbe08b12e81edc.pdf?index=trueIn 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_off0000e07a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE07A 5576 bytes
SHA-256: 90af5ded4d5f154ccdb2e85d3180b86b8411c17eb8a23b04297f4b23d2b896ef
font_01_sfnt_off0000f365.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF365 10860 bytes
SHA-256: 3f22274bfa42792dd1cf959f98eea9c8cf6f8c4c82c47d10a82056a67f96b9cc