Malicious PDF — malware analysis report

Static analysis result for SHA-256 23476b6c2b9151cd…

MALICIOUS

PDF

68.5 KB Created: 2021-03-01 22:31:37 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: f3654b3a1579d41080fd50de9bbfa1d8 SHA-1: 209bfdc18ffc3029a0abde61d39ba40a4206234e SHA-256: 23476b6c2b9151cdb6370fe8c5f0001e6bfde429cef8bc0939be482b52ea8491
184 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with several pointing to known malicious redirector infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though partially corrupted, contains text related to 'Ouku double din review' and 'wkhtmltopdf', suggesting a lure for potentially unwanted or malicious content disguised as a review or technical document. The presence of embedded URLs and the heuristic firings indicate a phishing or redirection attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://crophysi.ru/wix?keyword=ouku+double+din+review In PDF document text
    • http://nasty666.space/retrovirus_replication_youtubeofc7x.pdfIn PDF document text
    • http://bezigex.iblogger.org/bejurajujunevejuboraxek.pdfIn PDF document text
    • http://wonnaturila.space/nekozogejokasibanijuxaloru858.pdfIn PDF document text
    • http://montana-media.com/android_studio_jdk_directory6iwlx.pdfIn PDF document text
    • http://pukatasenibi.iblogger.org/pojakokunomebakib.pdfIn PDF document text
    • http://worigozuwujuva.iblogger.org/46245530644.pdfIn PDF document text
    • http://tefitagesev.mypressonline.com/relation_and_function_definition_in_hindi.pdfIn PDF document text
    • http://kanaxade.mygamesonline.org/36286168931.pdfIn PDF document text
    • http://waferaboteb.mypressonline.com/what_is_an_example_of_scientific_literacy.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://mosakokomu.epizy.com/physicians_desk_reference_2021.pdfIn PDF document text
    • http://fujuresaw.epizy.com/whatsapp_status_video_song_romantic.pdfIn PDF document text
    • http://remivipe.rf.gd/54730542231.pdfIn PDF document text
    • http://mulazukaga.rf.gd/dd_5e_icon_of_ravenloft.pdfIn PDF document text
    • http://rugokabiko.epizy.com/fabugetusa.pdfIn PDF document text
    • http://didigenekogama.epizy.com/sajani_kannada_movie_audio_songs.pdfIn PDF document text
    • http://logeger.rf.gd/mekojijijefibidesukufeg.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_off0000c42c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC42C 4616 bytes
SHA-256: 48f9df9dba194a0c717c4ea6516d0b6b1ddea8a1c70be9ef0d33845df4509b5c
font_01_sfnt_off0000d3e8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E8 10364 bytes
SHA-256: 605730977dafd56e224bcc0f53b271d7aa08c8003c4a040633181470bb30d295
font_02_sfnt_off0000f767.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF767 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3