Malicious PDF — malware analysis report

Static analysis result for SHA-256 136fe50f33c7ec69…

MALICIOUS

PDF

114.8 KB Created: 2021-04-17 02:56:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-25
MD5: 942bc9d4715a1f5cca0f65cdad1d7766 SHA-1: 0dc5c84589e1109846def73ab0ba2ebac8916528 SHA-256: 136fe50f33c7ec6920829411393441de3f55a6ae88fab255ac0f40c34c2eb5a1
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 0.9979

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://maypoin.ru/strik?utm_term=geometry+for+dummies+barnes+and+noble PDF link annotation
    • http://purpless.vip/blocky_farm_racing_and_simulator_mod_apk_download6gheb.pdfIn PDF document text
    • http://astropsychology.site/suwajiwub1it79.pdfIn PDF document text
    • https://tovunebutulewe.weebly.com/uploads/1/3/1/8/131871744/9102284.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4374848/normal_6017030b1b699.pdfIn PDF document text
    • http://nonly.xyz/george_foreman_indoor_outdoor_grill_smokeless4fse6.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4472182/normal_5fd178667eec7.pdfIn PDF document text
    • http://edalovert.xyz/kayaking_merit_badge_workbookymg3v.pdfIn PDF document text
    • https://zupuluduwiwafop.weebly.com/uploads/1/3/2/6/132681460/vedorekulimid.pdfIn PDF document text
    • https://filinisosiwox.weebly.com/uploads/1/3/0/8/130814007/zemelopikijava.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382201/normal_5fd82376174b8.pdfIn PDF document text
    • http://helplnstagram-confirm.com/13645817953e65lx.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4424376/normal_6069455bd8bea.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/18bb7c27-6e9a-4da6-8b59-39bc74a6c0f5/plan_de_estudio_2011_secundaria_educacion_fisica.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0f748a8d-0208-4851-9deb-41ac5e02682d/fajawuvamujaguxozerow.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8196826e-0cd3-4a35-911d-48ad3fdd4680/86537102686.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/cb3a3211-7eb5-4377-8de1-953d6f564dcc/kubapiwafududatiwesawu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/20663b5c-a092-4dea-a55d-03b434452ed2/81476726877.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/74a09a76-b933-4ebe-97b4-f49be0ce202a/whats_another_word_for_convention_center.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/530b1d9f-36c1-44fb-abdc-249f79d21c76/goliath_5e_wikidot.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/3c29d052-2f2c-4d93-8988-a36e9bc235e2/kenmore_coffee_maker_with_grinder.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/29297c73-a3ee-4a49-b93b-e1995d04a9ba/nosupu.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/ccc23039-1b99-4322-ba2b-09cfc8a0f508/bevez.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/366fcfe1-db46-4f2f-9237-a25a7d5e7efa/63115743648.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/7b78cf92-df5c-4a7e-bee2-31ba5e4b1e8c/lets_build_a_cladogram_worksheet_answer_key.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/18169278-3db3-46df-8c9a-385982639eb6/how_do_you_define_heavy_rain_in_mm.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_off00015afd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15AFD 5208 bytes
SHA-256: c7fc7943810c5464adda5db6f8e5a7e5fe342b5c732636cdff934c15b7be9d95
font_01_sfnt_off00016ca2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16CA2 13840 bytes
SHA-256: f95f6092cf23211da5526dc7994614f06dfb2c268f040327d4fce48ba2c43249
font_02_sfnt_off00019876.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19876 16428 bytes
SHA-256: 488ee1fef8d9fcf8b90908107b6c9065f7a97ed04d2b236b4fdbc9243ab4b9ef
font_03_sfnt_off0001aeb5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1AEB5 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333