Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8718d8da59f78b7…

MALICIOUS

PDF

81.7 KB Created: 2021-04-20 11:23:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-25
MD5: 3e9d6e9c39f785fefdf5ba03d6e04fef SHA-1: 10169f75b0a59fd08baedd3090eeaee3c2f9653a SHA-256: b8718d8da59f78b740a29746ea5a816dee8daf247a339fec9180cad69c68b095
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, indicating a link farm or SEO spam operation. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and numerous external links point towards an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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=what+is+manual+defrost+on+freezer PDF link annotation
    • https://molapoji.weebly.com/uploads/1/3/4/0/134096941/dunozidufebe.pdfIn PDF document text
    • https://zitavuzan.weebly.com/uploads/1/3/1/3/131379524/ribetiviw.pdfIn PDF document text
    • https://dubuvolikumo.weebly.com/uploads/1/3/4/0/134012832/fabozebigigo.pdfIn PDF document text
    • http://opt15.ru/xariteledik0klv4.pdfIn PDF document text
    • https://rogakaroguw.weebly.com/uploads/1/3/4/5/134517982/sevapa_dosilov_xuredidejokadi_welojijitosov.pdfIn PDF document text
    • http://zopaxonurur.iblogger.org/sufadodofozagudexapovez.pdfIn PDF document text
    • https://vesokawewewavi.weebly.com/uploads/1/3/1/3/131382886/juveka.pdfIn PDF document text
    • https://zedasadexim.weebly.com/uploads/1/3/0/7/130775923/602083.pdfIn PDF document text
    • http://itayoga.space/tudokalabexamea845.pdfIn PDF document text
    • https://lopuxewununoj.weebly.com/uploads/1/3/4/7/134748711/runuwoditumam-ranujejoziwig-zepusolanibut-mupajeka.pdfIn PDF document text
    • http://sollabs.xyz/5285144071956cun.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://gewumene.epizy.com/nepaxidunepu.pdfIn PDF document text
    • https://s3.amazonaws.com/kegubinefuda/kindle_fire_video_format_update.pdfIn PDF document text
    • https://s3.amazonaws.com/dukajevo/fajem.pdfIn PDF document text
    • https://86a9da1b-0b57-4b35-a77a-523886b904cd.filesusr.com/ugd/0d9a50_fff9091a445e487a841266892707a2c3.pdf?index=trueIn PDF document text
    • http://tezafafowajij.epizy.com/79747781548.pdfIn PDF document text
    • https://5ce19dfa-329f-495d-88d1-e1e7834d9072.filesusr.com/ugd/d902bb_96108a0fbe0b456fbbc6f48e8e12f969.pdf?index=trueIn PDF document text
    • http://lumolak.rf.gd/math_all_symbols_name.pdfIn PDF document text
    • https://s3.amazonaws.com/sorogamat/late_transition_metals_examples.pdfIn PDF document text
    • https://s3.amazonaws.com/xotomisen/introduction_to_computer_by_peter_norton_solved_mcqs.pdfIn PDF document text
    • http://toxalotivip.epizy.com/small_intestine_anatomy.pdfIn PDF document text
    • https://254b3b0b-79dc-4992-827c-fd4bb3db3178.filesusr.com/ugd/f515ca_a40cc7b1123945dc9111e1669cfa2ed2.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f6d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6D8 5092 bytes
SHA-256: 3954e74cd3a093c2668b60e58fe8e434ba56f22706822c33311d035120d29deb
font_01_sfnt_off00010809.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10809 10280 bytes
SHA-256: 7c6f0ea75e26f8416a801bf6ecb5ca25afb32c314a12bfaba28970f1a6e7078b
font_02_sfnt_off00012b3a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B3A 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3