Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa65330599d72fc4…

MALICIOUS

PDF

83.1 KB Created: 2021-03-28 15:08:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: aba23e275d3a88f659899ad048e2773b SHA-1: 23bed97a2c49fde963a154c6708c4cc4990b5a7d SHA-256: aa65330599d72fc43d864a317187a762db89e346e88180ad2500e4797b3becc1
186 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many hosted on disposable domains, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and link farm heuristic point towards an attempt to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 6

  • 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.
  • 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.
  • 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=install+setup.py+python+3
    • https://cdn.sqhk.co/guzowozuk/haibrie/vector_definition_in_computer_architecture.pdf
    • http://dabukim.mygamesonline.org/autodesk_revit_2020_tutorials.pdf
    • https://cdn.sqhk.co/luveruzosu/fjhzaIs/bubble_tea_game_review.pdf
    • http://lezigovedavide.getenjoyment.net/how_to_remove_battery_cover_from_liftmaster_keypad.pdf
    • http://xajabuzowa.scienceontheweb.net/60504167368.pdf
    • http://mofonuf.medianewsonline.com/24_makeup_brushes_and_their_uses.pdf
    • http://wulutano.mywebcommunity.org/fofexulogivatewa.pdf
    • http://gimemuwet.mypressonline.com/tijosezuvevuzu.pdf
    • https://cdn.sqhk.co/podidiwi/fhcgfha/rowetokizeji.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://0e01c86c-6ad9-43de-bc04-b8819f410213.filesusr.com/ugd/73c254_39796ac398eb4d838b90536ebc3a1643.pdf?index=true
    • https://e02212b7-c8ec-4bf5-ba3e-d68a1de675e0.filesusr.com/ugd/7f1d73_9f7287d34cbe443fad6e1d6505ab04b5.pdf?index=true
    • https://uploads.strikinglycdn.com/files/e936f7c3-8a33-4139-a1bb-cef615112212/94971837045.pdf
    • https://44f68060-d5e3-4d58-b4e7-e3760392f352.filesusr.com/ugd/49488e_bbc9f14213ff43919f69015158a2f5f9.pdf?index=true
    • https://uploads.strikinglycdn.com/files/fa5e6d55-1315-4a15-aab5-c9f2d2cfb5bf/dressage_intro_b_test_sheet.pdf
    • https://uploads.strikinglycdn.com/files/59e228c2-e8c5-4049-a8cf-845dbe115ab7/gexosome.pdf
    • https://uploads.strikinglycdn.com/files/e5db5b29-6322-40c3-8490-4b628b740a14/qsc_rmx_2450a_manual.pdf
    • http://pawuzax.onlinewebshop.net/bodyweight_circuit_workout.pdf
    • http://suduxegowur.onlinewebshop.net/pumites.pdf
    • http://pevogikuxupeja.onlinewebshop.net/dnd_character_sheet_online.pdf
    • https://3745348a-78a0-42d7-8ff4-af2b45bf5faf.filesusr.com/ugd/02631b_b920ad96523449e6b63c2ab8c6c3d72a.pdf?index=true
    • https://76c9fb28-c10e-4950-85be-37de24a2ede8.filesusr.com/ugd/fa32a6_91d300b42cd04df19d0516d713588c81.pdf?index=true
    • https://uploads.strikinglycdn.com/files/5f46300b-04f2-4254-b4ee-261ee572b64e/10974270334.pdf
    • https://d4f4546a-a836-4b3d-8651-c56b89608eca.filesusr.com/ugd/3e9e83_a352f7bd2ee34d5bb2bd8824a8c27771.pdf?index=true
    • http://tevaluzax.atwebpages.com/jaketi.pdf
    • https://9dc8676a-0e58-44ee-a512-e339c7094702.filesusr.com/ugd/7c0652_7447e41ce2d240d0997599a55e044f74.pdf?index=true
    • https://de7eff9d-5c50-4122-bb99-ee112abf7a8f.filesusr.com/ugd/db8f21_d2699e00326f4207a9f3e670005873f0.pdf?index=true
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001042c.bin
b4113ff0be4a2b5b5a6cad9cbc0f127cd5982eac1e93c76a1902ae3644a1967a
pdf-font-stream PDF embedded font (sfnt) at offset 0x1042C 5048 bytes
font_01_sfnt_off00011566.bin
be71b39c113c4c8142c68314214351691f2329d899a1e549547709c62d10b74e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11566 12180 bytes