Malicious PDF — malware analysis report

Static analysis result for SHA-256 3d1b71a21c4a91c2…

MALICIOUS

PDF

71.3 KB Created: 2021-03-05 09:05:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-03
MD5: 6b88593a95a5f31e3120ef5fb6455a38 SHA-1: 52b9c5a9703c1bec3633db30effb86c3faaf5856 SHA-256: 3d1b71a21c4a91c20b097c78aa717c0d123359ecb70f0844a4c9fcab10c2689a
186 Risk Score

Malware Insights

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

This PDF file contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to potentially harmful websites. No scripts were extracted, but the PDF structure itself is used to host and present these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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/award?keyword=material+science+and+engineering+book PDF link annotation
    • http://tebogekememesij.mygamesonline.org/what_is_executive_director_at_morgan_stanley.pdfIn PDF document text
    • https://cdn.sqhk.co/bexutavukaro/fBhejfA/jipelifinekusotutunuwe.pdfIn PDF document text
    • https://cdn.sqhk.co/munuluxel/RgUiuje/army_wallpaper_for_walls.pdfIn PDF document text
    • https://cdn.sqhk.co/bikegola/ajgxE1y/libusotarawijesul.pdfIn PDF document text
    • https://cdn.sqhk.co/satofapo/cicjeha/u_dictionary_app_for_pc.pdfIn PDF document text
    • http://najisemure.medianewsonline.com/pathfinder_race_ability_score_chart.pdfIn PDF document text
    • https://cdn.sqhk.co/goxobuve/Zynib3Q/tosadurapuvatolarib.pdfIn PDF document text
    • http://lumobumekola.getenjoyment.net/how_to_make_a_paper_finger_claw.pdfIn PDF document text
    • http://wutopezogegusi.getenjoyment.net/tilasorezokumogelegirufi.pdfIn PDF document text
    • https://cdn.sqhk.co/purorelaz/6jeMqNO/tojidewuwefemidugifapotet.pdfIn PDF document text
    • https://cdn.sqhk.co/sojowidaz/hgwxhe4/wemovirobawisikotusosibun.pdfIn PDF document text
    • https://cdn.sqhk.co/gubisagebuto/idEiehb/crash_townsville_today.pdfIn PDF document text
    • https://cdn.sqhk.co/givesaxi/haWgigc/triple_crown_races_2020_running.pdfIn PDF document text
    • https://cdn.sqhk.co/bexuxoxabim/iiChbje/rush_hour_1998_full_movie_youtube.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://zitasixan.atwebpages.com/nothing_can_change_the_shape_of_things_to_come_movie.pdfIn PDF document text
    • https://s3.amazonaws.com/tanikanaw/34762627600.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/83e8b07b-5a16-460c-b298-f678ae86ab0a/piderugepabuvibopog.pdfIn PDF document text
    • https://5a98ae10-8c7e-48da-b83f-9bcbc644cfa3.filesusr.com/ugd/9a8764_5aa124c055884c4aa6cfe653d7b3a4f5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/f4b515ba-335c-4237-a973-06404e4afce7/mogomezeremufopojeraf.pdfIn PDF document text
    • https://e8c82854-2a0b-4c0f-82de-bac600ce06e6.filesusr.com/ugd/d017d5_13df66062110460c832a21d210a7b0f4.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/xofalepelala/essential_oils_uses_guide.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cf8fe016-0753-4a5e-9dfe-004c681a89aa/amazon_kindle_model_d00901_critical_battery.pdfIn PDF document text
    • https://528a8416-53f4-4693-bcf0-540471887af1.filesusr.com/ugd/c3aa89_2cdaed85c9fe4c159c9dac1101dda45c.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/a36a0dd1-312e-4348-b28d-7da2d0335656/how_to_interpret_a_financial_ratio_analysis.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_off0000d8ee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8EE 5316 bytes
SHA-256: b51f5c60d4816dcc1acbff4a9232f57f34bbd7802d56f3d0c4659a725bbda039
font_01_sfnt_off0000eb19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEB19 10844 bytes
SHA-256: 2dfaacdcd1ebc0d852feb7cf7d773a820b6551ba4c53d7b35a0bf60f1027be38