Malicious PDF — malware analysis report

Static analysis result for SHA-256 d43f7604a351bbb1…

MALICIOUS

PDF

85.2 KB Created: 2021-04-08 02:35:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: ad2c8cf71782c3eb86146b50e2c4e2d7 SHA-1: b2c39b234d56f75e8603e45fff059888ab901f23 SHA-256: d43f7604a351bbb187ef6c62fbb38487718e8f98e8ea966f005a7cb503145711
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 0.9998

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://baarspo.ru/strik?utm_term=where+is+atp+stored+in+the+cell PDF link annotation
    • https://favimorujupufu.weebly.com/uploads/1/3/2/7/132710565/b280bc939.pdfIn PDF document text
    • http://xonigej.mypressonline.com/87372588234.pdfIn PDF document text
    • http://dobilarujokux.sportsontheweb.net/99401065215.pdfIn PDF document text
    • http://deteluwo.iblogger.org/pelayanan_rawat_jalan_adalah.pdfIn PDF document text
    • https://sojanonef.weebly.com/uploads/1/3/0/9/130969598/d933b7ea1ac0.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://bb491b24-4c81-4ccc-8daa-bf1baeb171c2.filesusr.com/ugd/93c935_9b641d0614c7477382a8b43e384ab0b3.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/ced0c172-c4ab-4dd7-8cb7-58cb2f28e1c9/79594025191.pdfIn PDF document text
    • http://pasulupumorowim.myartsonline.com/oxford_dictionary_free_download_full_version.pdfIn PDF document text
    • http://muxoridevifi.epizy.com/23438177573.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/1dc438dd-7846-436e-9fd7-8cc4295e1129/wonemorevepepaluluwagum.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/340e69d6-3753-43fc-887b-186f5edcd1d0/2006_toyota_sienna_heater_hose_connector.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c94358b7-32bb-483c-b17d-f0d709f2229f/xisekirilegififinu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/701bfb6c-9c6c-432b-87f2-823d52bff3f6/how_to_adjust_gas_water_heater_thermostat.pdfIn PDF document text
    • https://5e20aa6b-77ef-4f11-9344-5454fb7c649c.filesusr.com/ugd/fb3aa9_4845f83104f94647baea0bc829cbfcbc.pdf?index=trueIn PDF document text
    • http://mexefesu.epizy.com/what_are_the_four_rules_of_fractions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/05da3ee9-5338-4ebe-b078-263f6dac2a3a/is_it_safe_to_use_air_conditioning_during_covid.pdfIn PDF document text
    • http://bemogabidemixu.epizy.com/ruud_silhouette_2_gas_furnace_manual.pdfIn PDF document text
    • https://aed022ca-8a9d-452d-9022-56a74a585a14.filesusr.com/ugd/4d548e_cc11baf199cc4ca88f1a0b1a79f39b96.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/69a45a2e-098a-4530-a542-a4ee82fe9eb6/how_to_clean_a_thermador_gas_oven.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000faa2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFAA2 5176 bytes
SHA-256: 198c3888f1f58f85152e9a90430904e1adce36ed2b7f037a8dbe4e7fc76e4888
font_01_sfnt_off00010c43.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C43 11176 bytes
SHA-256: ce02ee8df53b8d47acb85ef751f15ef20c4349b267289e9a80b542ab599a2354
font_02_sfnt_off0001325b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1325B 16204 bytes
SHA-256: a95eff378c135b1ab40d10b3cd1da1bafbc07f86005f57898d079c90d712ddbd