Malicious PDF — malware analysis report

Static analysis result for SHA-256 d485a235250d4c38…

MALICIOUS

PDF

90.7 KB Created: 2021-03-16 20:54:26 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 9d9b3d4a666e708427c6c0f700a53b83 SHA-1: 954142beeebf242852d52b541ff0aa4751ad1249 SHA-256: d485a235250d4c384f35e928f0340c2f09eb1a7ecd20afb24cd5a7baeca3efcb
186 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://fokemale.ru/strik?utm_term=sunflower+oil+formula PDF link annotation
    • https://static.s123-cdn-static.com/uploads/4386851/normal_5ffb07b20aa87.pdfIn PDF document text
    • http://fudoviwil.mywebcommunity.org/bsc_1st_year_zoology_notes_2020.pdfIn PDF document text
    • http://penexej.mywebcommunity.org/87504114643.pdfIn PDF document text
    • http://jokebixa.22web.org/azure_service_bus_connection_string_arm_template.pdfIn PDF document text
    • http://rejamar.sportsontheweb.net/adding_and_subtracting_proper_fractions_worksheet.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4425009/normal_5ff21ea94c681.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4448992/normal_6043dce0b21d0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://wovuluvoju.onlinewebshop.net/mugokaw.pdfIn PDF document text
    • https://04934832-22f3-474e-96de-b9d593e92251.filesusr.com/ugd/f390e7_0e209fa4af474f6988228fb4bd824bef.pdf?index=trueIn PDF document text
    • https://1fa67a36-2e8b-44cc-a955-751d80433762.filesusr.com/ugd/d85e51_df11b3ec47464044ad6e73de16c2cd90.pdf?index=trueIn PDF document text
    • http://tikomiwewo.atwebpages.com/ejercicios_agudas_llanas_y_esdrjulas_4_primaria.pdfIn PDF document text
    • https://87164119-88a6-4d6d-a72f-b109cf2d88b9.filesusr.com/ugd/bd0a66_b3c24d2de85f40dfa0ec962ae833bb30.pdf?index=trueIn PDF document text
    • http://nisebot.epizy.com/bavogujas.pdfIn PDF document text
    • https://d71fc03c-aea6-48f7-a990-8afffb22108d.filesusr.com/ugd/3de8a6_a84eddb1283445da8f4daf7f39a5418a.pdf?index=trueIn PDF document text
    • https://4d8de7df-eaaa-4cdc-85fb-7bbdf9a14b6f.filesusr.com/ugd/6166c9_9712734e7fcc4bc2974315643751d8fa.pdf?index=trueIn PDF document text
    • https://ad843f61-c544-48d7-8cfb-3c048b9edb46.filesusr.com/ugd/0dd9ed_c23908993d4243c5a971e89849691ccc.pdf?index=trueIn PDF document text
    • http://fesitakisuwizun.rf.gd/zamigoparoworusuwexok.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00010371.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10371 3052 bytes
SHA-256: 77de4c804aa2bd8363e23ef31f1ba3066ef5b5c17e00e074c944fc769f9f804e
font_01_sfnt_off00010e48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E48 4932 bytes
SHA-256: 373c7572af774777c7579c4ef0193eb446d928fb0a55fb89531c651179209403
font_02_sfnt_off00011f07.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F07 11868 bytes
SHA-256: 972a71fd3a9b5608667c29c2325b2f16e74e749ca7636f23f9904847652416eb
font_03_sfnt_off0001478b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1478B 16320 bytes
SHA-256: dadea3999a0090b27e3a6253b91094cd6480e5e5cac974bfba809f84143d080e