Malicious PDF — malware analysis report

Static analysis result for SHA-256 4d84f73e5b7c4999…

MALICIOUS

PDF

70.6 KB Created: 2021-02-28 08:54:24 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-07
MD5: 2d7e4727918c453e44ed4c14a5f8152f SHA-1: df3f05d9dbd5644a28228690c70dcc1415c20a37 SHA-256: 4d84f73e5b7c4999af0ed7bb1bca89edbaa516ec0f3a61c9615e9355a7b36c33
134 Risk Score

Malware Insights

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

The PDF file contains heuristics indicating it is a link farm and has been flagged by ML classifiers and ClamAV as malicious. The embedded URL 'https://bologen.ru/strik?utm_term=twin+star+electric+fireplace+heater+not+working' suggests a phishing or redirection attempt, disguised as troubleshooting information. The document body, though heavily obfuscated, contains text related to the lure. The presence of external URIs and the nature of the heuristics point towards a phishing or malware distribution vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=twin+star+electric+fireplace+heater+not+working PDF link annotation
    • https://cdn.sqhk.co/zabeluzitema/FOhecl7/pofapifomufezilobibenitu.pdfIn PDF document text
    • https://dupudebokuvufex.weebly.com/uploads/1/3/2/3/132303235/periragapeme_xatasaginotosuj_gavimule_tisovab.pdfIn PDF document text
    • https://cdn.sqhk.co/mevutaxisut/ghj4whj/wesedagumoguwulelovapive.pdfIn PDF document text
    • http://buvinivu.iblogger.org/yamaha_hs8_pair_review.pdfIn PDF document text
    • http://zitutetek.22web.org/compilers_and_translators_questions_and_answers.pdfIn PDF document text
    • http://sizijevoji.iblogger.org/bodo_album_2018_video.pdfIn PDF document text
    • https://kasikijafeke.weebly.com/uploads/1/3/1/4/131406722/wovinisa.pdfIn PDF document text
    • https://nakumupapetiz.weebly.com/uploads/1/3/2/7/132741615/wisazagafemaxajoz.pdfIn PDF document text
    • https://xevumijujivo.weebly.com/uploads/1/3/1/3/131383583/4733241.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://vutesupazidoz.epizy.com/86375124612.pdfIn PDF document text
    • http://felawikemuda.epizy.com/haloperidol_mechanism_of_action.pdfIn PDF document text
    • http://bolarerovu.epizy.com/aadhalal_kadhal_seiveer_songs_in_tamiltunes.pdfIn PDF document text
    • http://vogojitipam.epizy.com/mad_world_sheet_music_piano_easy.pdfIn PDF document text
    • http://sanejiwobar.epizy.com/93618558725.pdfIn PDF document text
    • http://fetufebutegiv.rf.gd/car_games_for_kids_boys_for_pc.pdfIn PDF document text
    • http://xaviwawav.epizy.com/wifi_connect_button_disabled_in_android.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_off0000d87f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD87F 5380 bytes
SHA-256: 728c9e2f450f0a8c2bfe7693130c9d2b59e385ded3a3c81a2ef6a92db0f9a0f8
font_01_sfnt_off0000eadc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEADC 10040 bytes
SHA-256: 4d31f774c3cbe9006d9f02782afd718f7a36c3febc2b35cf12abb4bbb37af07b