Malicious PDF — malware analysis report

Static analysis result for SHA-256 2467aa08b5f1ae47…

MALICIOUS

PDF

80.4 KB Created: 2021-03-17 11:34:24 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 5a5cd1089cf0de5e21fa6e42ccc17da3 SHA-1: 21e28aef765217f53aa65eddc679402a78d851fa SHA-256: 2467aa08b5f1ae47c91ca4527b935221ce9bceb1c1c4c9811b3f89cbaa9b1e76
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, identified as a link farm, with a primary URL pointing to 'kuzutuzo.ru'. This behavior, combined with ML and ClamAV detections, strongly suggests a malicious intent, likely to redirect users to phishing or malware hosting sites. Although no scripts were explicitly extracted, the PDF structure and heuristic firings indicate it's designed to facilitate malicious redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9994

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=how+do+you+eat+a+whale+quote PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4489042/normal_60248e3eb0c1f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4446762/normal_604d925ece837.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488322/normal_602452ceb0223.pdfIn PDF document text
    • http://jomokanus.22web.org/time_capsule_ideas_for_babys_content_first_birthday.pdfIn PDF document text
    • http://rapegupuv.iblogger.org/wilinitexejajagujiro.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424330/normal_602aa59c634aa.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4455881/normal_5fddfda6b57d2.pdfIn PDF document text
    • http://lefuvaguvupawax.iblogger.org/57756130507.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4482869/normal_5fca929419fa5.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/525ebc8b-13b0-424e-ba26-4646b8437dd4/fiminujusovixid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/2bbefe5e-d0b6-48f5-b264-7ed5b1826a2e/59841299064.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0c3b3ee2-51c7-4a2e-b047-60b529a551fa/34367382314.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/76df0245-3973-4f7c-bcfe-64952b483cf6/93640665819.pdfIn PDF document text
    • https://18b09f4e-de4d-4c1b-9fe6-be55c63b1c00.filesusr.com/ugd/cd81e9_a9801f20551b41f4a3312dfadd9fd36f.pdf?index=trueIn PDF document text
    • https://d668ac4b-7052-46b9-8d0c-7e282d24ced7.filesusr.com/ugd/00fc84_5c8d3e2b331a4f9c9f427bfb6b648867.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/626e2e14-1ae4-4252-ba33-b0335535d7ba/hp_elitedesk_800_g1_tower_video_card_upgrade.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/b8bb6edd-8b7b-4ad8-a798-dfe10e164606/wedofitixixoguzej.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1238ea47-6d98-4cdb-acef-44a363923a41/resumen_corto_de_los_hermanos_karamazov.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/f070ef45-9094-43b1-ae72-c8b70a12eff4/rolojajuseb.pdfIn PDF document text
    • http://fipabazubigu.rf.gd/zejizunuje.pdfIn PDF document text
    • http://nobibovadov.rf.gd/mmpi_test_questions_answers.pdfIn PDF document text
    • https://0296ecfc-28ae-4fa5-925c-67a25994cace.filesusr.com/ugd/c88839_77768e1ab7ed4a4da375fc82bdb820d1.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8cc398e0-e875-4635-9d58-681679bbd41e/wibavamijuxoririti.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_off0000f9a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A8 4920 bytes
SHA-256: 81f9069d87344e984443cef40e66dba7d536f33937903637c358d6c2cb95d895
font_01_sfnt_off00010a73.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A73 11812 bytes
SHA-256: 5f26c148631d4b5c3845d095a7b09f30e7b92c553814db14d69f62232cc85cfc