Malicious PDF — malware analysis report

Static analysis result for SHA-256 042563d07acbe62b…

MALICIOUS

PDF

82.2 KB Created: 2021-03-29 12:14:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 1d0b72374f3517dab04d7ccf5ba79ea7 SHA-1: 22b2ba2d2b70b0aabd116809e8d6221e382bc3f2 SHA-256: 042563d07acbe62ba050d95bc3b9aaeb4d9e86ab39cdb6771e0f4d1694eb7af9
186 Risk Score

Malware Insights

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

The PDF contains a mass external link farm, with many links pointing to disposable hosting and using UTM parameters, indicating a phishing or ad-revenue generation scheme. The ML classifier and ClamAV detection strongly suggest malicious intent, likely to distribute further payloads or lead users to phishing sites. No scripts were extracted, but the PDF structure itself is indicative of a link farm attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://jacksth.ru/strik?utm_term=concrete+mix+design+csi+code PDF link annotation
    • https://cdn.sqhk.co/logubaxe/dv59jhQ/88982350760.pdfIn PDF document text
    • http://jovepodixowofow.mygamesonline.org/20768711100.pdfIn PDF document text
    • http://befotuke.mywebcommunity.org/geronimo_stilton_season_3_episode_1.pdfIn PDF document text
    • https://cdn.sqhk.co/wemojezuvegi/hbHhaid/coffin_nails_designs_2019.pdfIn PDF document text
    • https://cdn.sqhk.co/muwupajikaro/P3gcyhj/furozu.pdfIn PDF document text
    • https://cdn.sqhk.co/nanuvoxeva/gemgifM/run_android_apps_on_windows_phone.pdfIn PDF document text
    • https://cdn.sqhk.co/litigoruf/gfigfnS/best_hits_of_ac_dc.pdfIn PDF document text
    • https://cdn.sqhk.co/nurijodefa/hNTvajc/absolute_monarchs_worksheet.pdfIn PDF document text
    • https://cdn.sqhk.co/nogojexibawa/74dibje/79407218821.pdfIn PDF document text
    • http://bekopomulasebi.getenjoyment.net/online_ms_word_document_editor_free.pdfIn PDF document text
    • https://cdn.sqhk.co/xadelakora/fjdGAfm/kipavawagoxutoxabumupiz.pdfIn PDF document text
    • https://cdn.sqhk.co/pamomusemida/fhfqchb/bc_hydro_smart_meters_health_concerns.pdfIn PDF document text
    • https://cdn.sqhk.co/nonuripot/chemXwQ/virus_scan_failed_webroot.pdfIn PDF document text
    • https://cdn.sqhk.co/bozutebux/hn5ghoU/66201604851.pdfIn PDF document text
    • https://cdn.sqhk.co/lamajemomu/jaiiggI/79904763977.pdfIn PDF document text
    • https://cdn.sqhk.co/vitimosugu/Hjfjdjg/foosball_table_dimensions_plans.pdfIn PDF document text
    • https://cdn.sqhk.co/ralofobo/gHgjTig/mcq_book_for_computer_science.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://feferabi.atwebpages.com/how_to_write_an_analysis_paragraph.pdfIn PDF document text
    • https://s3.amazonaws.com/wizitifowubux/addendum_document_template.pdfIn PDF document text
    • https://s3.amazonaws.com/tesotiwapax/guxova.pdfIn PDF document text
    • https://s3.amazonaws.com/tinezedu/80330479778.pdfIn PDF document text
    • https://22e44a25-5b44-49ab-8bd1-9de78d2943b2.filesusr.com/ugd/cce535_259c1df1e63e47ea9349ddb8627a6ebc.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xajowu/fixezafipodakor.pdfIn PDF document text
    • https://69a21580-3c80-4f81-8097-1ec0bc18215d.filesusr.com/ugd/bd7df1_d19fc4d9199247708b5700266254e033.pdf?index=trueIn PDF document text
    • https://18aefb47-0221-41c7-ace0-4f78eb33e730.filesusr.com/ugd/bca722_e04850ced5064bfeac4eb75c51120413.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001068e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1068E 4992 bytes
SHA-256: 6e5bb32284e271eb3cc887574a06320111d0beaab3e5a4710030135c3cbd22c1
font_01_sfnt_off00011773.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11773 10472 bytes
SHA-256: 1072c8341202b39cfe23eb951bef7595395e9ebbf5e557640b19fecd16fbb9bf