Malicious PDF — malware analysis report

Static analysis result for SHA-256 b774a09fd3546528…

MALICIOUS

PDF

88.4 KB Created: 2021-03-21 09:43:23 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 2fc293a07be3f39111c473c164547423 SHA-1: c3880f765b48b55c27b3c43311b76cc7978cbb3f SHA-256: b774a09fd35465288dabfcf4608bdbe8d8832eab124a2dae152a40870a132903
186 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, many hosted on disposable domains, indicative of a link farm. The presence of ML and ClamAV detections, along with the PDF_SEO_LINK_FARM heuristic, strongly suggests malicious intent, likely for phishing or malware delivery. While no scripts were directly extracted, the embedded URLs are the primary indicators of compromise.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

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://kuzutuzo.ru/strik?utm_term=mi+maestro+el+cient%25C3%25ADfico+estaba+feliz+de+que+yo PDF link annotation
    • http://felagem.getenjoyment.net/59027196627.pdfIn PDF document text
    • https://cdn.sqhk.co/limizolaxa/I9cc0ic/gunodisinebatebazeguda.pdfIn PDF document text
    • https://cdn.sqhk.co/lisakopew/ixgiiaz/38121165328.pdfIn PDF document text
    • https://cdn.sqhk.co/nonatedogo/MBRgi7j/defender_hd5_forum.pdfIn PDF document text
    • https://cdn.sqhk.co/niserutom/KgfNihL/pupulepajukuzapanab.pdfIn PDF document text
    • https://cdn.sqhk.co/dipujabuxiw/agctqjg/deriving_risk_neutral_probabilities.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
    • http://sopavame.onlinewebshop.net/52933491466.pdfIn PDF document text
    • https://7ef7ebf0-bcb0-4ca2-8538-5a19c3e9f01c.filesusr.com/ugd/aff7ca_cfc186eb7e33405b963a9334023f20b3.pdf?index=trueIn PDF document text
    • https://fdb4f28e-c637-431f-967d-457feef73efb.filesusr.com/ugd/cf5aa9_c53804db37f14d85a3fc8d6001cce89e.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ceecfc98-d1c2-478e-829b-b6444c6fa856/tisafesubijikipumoladoga.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7ed8bc0d-2d39-4300-89d3-16b02ee07d40/6476530147.pdfIn PDF document text
    • http://banudozege.epizy.com/hellfire_ring_guide.pdfIn PDF document text
    • https://a2214900-82f6-4ed5-a432-d5ffd14110fa.filesusr.com/ugd/306b6b_6f834b84bd9343ea8f3375818bd02291.pdf?index=trueIn PDF document text
    • https://21319658-e817-4d6a-846f-872ccfe0f0c2.filesusr.com/ugd/982af2_79ef097705f54ad39cd52178e60cf618.pdf?index=trueIn PDF document text
    • http://xutulatovemi.epizy.com/96086927824.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/168b343c-0e5b-4b8d-a219-d68ef622b556/juwezimexazev.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8108c51-b613-4128-bffc-c4acd020263e/shark_apex_powered_lift_away_vacuum_cleaner.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/da26b2d8-4efd-4f1d-a90f-1b52828cc53d/61776774894.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7a3be802-45d3-47f3-bd6c-13d5f79e3d91/spanish_to_english_dictionary_book.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d77ed9ca-bfcd-437a-9b3e-8b978a9fecef/sajunafalufur.pdfIn PDF document text
    • http://wuzorijo.rf.gd/ninipebalaxavemudavasabo.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/440a76ab-2765-432e-9ff0-8068b2a574c5/technics_sl_d20_turntable.pdfIn PDF document text
    • http://vawofirulev.myartsonline.com/list_of_countries_and_their_capitals_download.pdfIn PDF document text
    • http://duvaneloxa.epizy.com/data_structures_and_algorithms_in_cpp.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b76b1e13-9117-4177-bcd5-290b6ba37082/how_to_use_water_softener_pellets.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_off00010a7e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A7E 5528 bytes
SHA-256: b581e86434d109e6205347808aa15762b691778a5f9c5f43cda88043db584f83
font_01_sfnt_off00011d39.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D39 11636 bytes
SHA-256: cfecdfc0ce050c60013cdf024b19331fc5c07ce23021fdcd5340e9513f7413d2
font_02_sfnt_off00014375.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14375 4324 bytes
SHA-256: d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378