Malicious PDF — malware analysis report

Static analysis result for SHA-256 2c81e4c0f8bb4860…

MALICIOUS

PDF

75.1 KB Created: 2021-05-22 11:19:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-22
MD5: 5936d093c0d17d9343fa47a835344101 SHA-1: d7ee35ab319c9fc264d400cbf27a50423929c276 SHA-256: 2c81e4c0f8bb486042e174ba2b1d00b673383a7a08cc2c70ef2687062ef6fa21
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. 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 0.9991

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://fokemale.ru/strik?utm_term=pharmaceutical+organic+chemistry+1+book+pdf+download PDF link annotation
    • https://menajogatidufe.weebly.com/uploads/1/3/0/7/130740573/tejawo.pdfIn PDF document text
    • https://wutosalix.weebly.com/uploads/1/3/4/6/134635680/jonadope_nuxipe_rapupekotidesed.pdfIn PDF document text
    • https://kuxobemif.weebly.com/uploads/1/3/1/3/131379353/8939836.pdfIn PDF document text
    • https://welajewovire.weebly.com/uploads/1/3/3/9/133999455/3351377.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4494431/normal_5ffb24d57a0ca.pdfIn PDF document text
    • https://jizexukufi.weebly.com/uploads/1/3/4/1/134109318/poxakakokuzak.pdfIn PDF document text
    • https://vakexojukesazi.weebly.com/uploads/1/3/0/9/130969985/733957.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4410191/normal_6015309ad4ffa.pdfIn PDF document text
    • https://dujibirarikow.weebly.com/uploads/1/3/4/3/134321406/5586025.pdfIn PDF document text
    • https://relitemora.weebly.com/uploads/1/3/4/3/134352419/marenowubi-sawegamumu-pariw.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4443371/normal_603189a759e2b.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/48be71bb-5633-4e06-a756-3ef82b73952b/how_to_make_a_server_in_minecraft_tlauncher_1.16.4.pdfIn PDF document text
    • https://s3.amazonaws.com/legenapi/nidijurod.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dbef6431-be9e-47f1-83f0-7a434af4dd85/97843366343.pdfIn PDF document text
    • https://s3.amazonaws.com/jepavilutabilel/tegobibire.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6f6031ed-cf49-41e0-80e2-1311c5f2b214/new_york_state_dmv_permit_requirements.pdfIn PDF document text
    • https://s3.amazonaws.com/mexavofezoxi/cra_report_gst.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e5cef74c-363e-4516-a150-3e1e1ac58063/suxopuradox.pdfIn PDF document text
    • https://s3.amazonaws.com/xidulumexi/kiruduzigulajise.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cc06a3f2-dd3a-4f22-a649-6b5932f8a6e5/eoc_algebra_2_practice_test.pdfIn PDF document text
    • https://s3.amazonaws.com/zonebon/ubuntu_14._04_64_bit_iso_image.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/330d5429-7cd1-4b61-b47a-cb51501a5955/vexupasodaxujuratilige.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e8811f8b-b90f-4f45-a750-e9daf87a7067/cessna_150_parts_for_sale.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/53de86b7-c600-4c74-9d56-f95e05455d73/pretty_little_liars_books_in_order_to_read.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_off0000e66a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE66A 6020 bytes
SHA-256: 7a1909eda46bfb964342ee4f25ba087a3b2bbd4eb35e791de18668fd9a2e2fa1
font_01_sfnt_off0000fadb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFADB 10384 bytes
SHA-256: 247de82aae8105cd5a6e8fd1a94891cb0962592acd99ef41e87d67ba65e79d8b