Malicious PDF — malware analysis report

Static analysis result for SHA-256 b26ddc38cddb3f58…

MALICIOUS

PDF

80.9 KB Created: 2021-05-28 06:10:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-23
MD5: 20593ba9f10a6c2b6ed95c3e373f57cb SHA-1: 1781636ba474deea5731d5393a5ca21887696ead SHA-256: b26ddc38cddb3f5829ddad514f8ee9077ba73fc6e9303395156088e0bcfa4d02
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 0.9994

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://jumiwimov.ru/strik?utm_term=duplicado+certificado+bachillerato+ceneval+acuerdo+286 PDF link annotation
    • https://cdn-cms.f-static.net/uploads/4471513/normal_606479573f74c.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4498702/normal_605ce9db2ffb3.pdfIn PDF document text
    • https://bijazebis.weebly.com/uploads/1/3/1/3/131382141/xoxedu_nokobafig_midivikep_xufafesamoxade.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4460241/normal_604f7c72368fa.pdfIn PDF document text
    • https://farupixin.weebly.com/uploads/1/3/4/3/134314126/sopenu.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370092/normal_60339f3487bf2.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4481834/normal_601f59b1121a1.pdfIn PDF document text
    • https://pusakinadolelu.weebly.com/uploads/1/3/2/6/132682110/fepafegufo.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4416805/normal_5fd7161867cc1.pdfIn PDF document text
    • https://puzuzabijil.weebly.com/uploads/1/3/2/8/132814257/degin.pdfIn PDF document text
    • https://makukojubava.weebly.com/uploads/1/3/0/7/130739489/e77b9.pdfIn PDF document text
    • https://tazizepi.weebly.com/uploads/1/3/4/4/134439401/3941669.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4498702/normal_6053581d74a27.pdfIn PDF document text
    • https://tegikalom.weebly.com/uploads/1/3/0/8/130874380/levumodesawemak.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489844/normal_60241ec96f9f9.pdfIn PDF document text
    • https://povefedonigo.weebly.com/uploads/1/3/1/6/131637150/fusugotokagi_kinivudibik.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/08e987cd-92d8-4d7d-b6fe-0221b8750c3a/juwunidegimovanupi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6fcd2ba8-a72a-4088-aefd-ccaa5ac00195/68642644066.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a03a08e7-e2c6-4d79-9271-a0aeac2e3327/digital_design_mano_5th_edition_solutions.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4f5ad0c5-dd24-4a08-84a6-f782f972c07b/how_much_do_farm_irrigation_systems_cost.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/5f038ba8-3603-4925-8107-59e0ff660916/65714225787.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4e8a4ad6-84eb-4884-8798-98655df27990/reset_linksys_re2000.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8632c8cc-2e52-4136-911e-4a7f8ef8be95/52489184693.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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF744 5744 bytes
SHA-256: beb50ff2275a88e66267e74614d9534b1d6357d2ae696ed4cc83b6e7b9bff160
font_01_sfnt_off00010ad4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AD4 13436 bytes
SHA-256: 0248d1d2adef103cb9a51c21fd3a7fe0b798bc5e8142eda85b0d943cc5a103bc