Malicious PDF — malware analysis report

Static analysis result for SHA-256 a97aad3d45ba132b…

MALICIOUS

PDF

75.5 KB Created: 2021-03-31 08:34:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-20
MD5: d9f2cb2371ce608fcce36e7f84192adb SHA-1: 7f0241025ded4872c3975c937c223bf95a459103 SHA-256: a97aad3d45ba132b78acb49a487467f498c60b3170e756190e19641c559720f0
186 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous external URLs designed to redirect users to potentially harmful content. The PDF_SEO_LINK_FARM heuristic specifically identifies the presence of a mass external link farm within a small PDF, suggesting an attempt to manipulate search engine results or distribute malware through deceptive links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://nipisod.ru/award?keyword=uranyl+oxalate+actinometer+pdf PDF link annotation
    • http://rabiwitijif.medianewsonline.com/kukuwuzopalipuguwiveti.pdfIn PDF document text
    • http://zabovawupe.mypressonline.com/anatomia_y_fisiologia_de_ano_y_recto.pdfIn PDF document text
    • https://cdn.sqhk.co/ditetijesi/ji7gjwN/20_levels_of_code._org.pdfIn PDF document text
    • https://cdn.sqhk.co/jidelugob/dhfiiih/bullet_rush_game_online.pdfIn PDF document text
    • http://buvalopexur.mygamesonline.org/fomerodizupexabiso.pdfIn PDF document text
    • http://wejaduz.mypressonline.com/performance_culture_and_athenian_democracy.pdfIn PDF document text
    • https://cdn.sqhk.co/mipijotom/iegj2wm/vr_zombie_town_3d.pdfIn PDF document text
    • http://rutinesuzufogat.mypressonline.com/ancient_greek_timeline.pdfIn PDF document text
    • http://losopefopamusoz.sportsontheweb.net/90194193613.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://87b84290-c0b3-4c73-97a1-3d59c64c3f69.filesusr.com/ugd/c638b7_d98846294c7647319a9a6ecd95f23fc7.pdf?index=trueIn PDF document text
    • https://e29f0852-aa8c-4fc4-a5db-fcd144ab7086.filesusr.com/ugd/b730be_a1bcecf75c7f4c14978317b2f616ba70.pdf?index=trueIn PDF document text
    • https://2863666b-9d79-467d-9aad-9eeb6dafbdf2.filesusr.com/ugd/6ee3eb_faff8b6fe97d4f43910ff3998b065998.pdf?index=trueIn PDF document text
    • http://tameladizikep.atwebpages.com/english_language_techniques_worksheet.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/26910529-6957-49e9-a148-58b09c78f7c6/jajozimowoxipobitamap.pdfIn PDF document text
    • https://66547991-fb4b-492c-b271-2b6457db34f0.filesusr.com/ugd/a98e70_34cb9f16df1a43e698e4de6e2db1443c.pdf?index=trueIn PDF document text
    • https://0ed30ddb-3df1-4505-9e4e-3e87fc6d20ea.filesusr.com/ugd/f043c1_9418c677c2024f63b31456994196d400.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/86f4dcd2-e9ce-4d4f-99a5-1db7585e9192/sojejuzexiveri.pdfIn PDF document text
    • http://kojenixerog.myartsonline.com/cambridge_primary_checkpoint_past_papers_maths.pdfIn PDF document text
    • https://1cbf0fd9-62af-4102-a3dc-982f361539e7.filesusr.com/ugd/bfbc46_392219ad2e104011a2d2431e3d1e8dc9.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_off0000ead3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEAD3 5284 bytes
SHA-256: 165e0ec57f029e437d395f91884a36bb3e0f0effa5899c16ca1a78af464f7ee8
font_01_sfnt_off0000fcca.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCCA 10636 bytes
SHA-256: 26f86aac5b8580318eb8443e86e5ae78e9f99a27c0ddada4f2f841294d649bda