Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1f8df16bd1b936f…

MALICIOUS

PDF

84.6 KB Created: 2021-03-27 16:39:42 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-06-30
MD5: b219de8ec687bb78ed7ae239e17088f2 SHA-1: 5910816fc430fe2dcedcce27bbf390c5d6831e9e SHA-256: d1f8df16bd1b936f9b5d3be9a51afff4d3b48139c68df0ac54a8e9a5ff5ad38a
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many hosted on disposable domains, suggesting a link farm or SEO spam operation. The ML classifier and ClamAV detection strongly indicate maliciousness, with the PDF_SEO_LINK_FARM heuristic pointing to a large number of external links. While no scripts were explicitly extracted, the presence of external links and the overall structure suggest an attempt to redirect users to malicious or spam content, likely initiated via spearphishing.

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://jacksth.ru/award?keyword=acta+constitutiva+pdf+para+llenar PDF link annotation
    • http://repair-monokoles.ru/jeffreys_bay_surf_report_windguruebyt3.pdfIn PDF document text
    • https://lefizedut.weebly.com/uploads/1/3/2/6/132681647/zerewuzifibiguz.pdfIn PDF document text
    • http://idealica-official-it.website/how_to_use_ge_profile_advantium_120dhm6b.pdfIn PDF document text
    • https://wuvumivew.weebly.com/uploads/1/3/1/4/131410662/3895144.pdfIn PDF document text
    • http://biomaniks.website/que_quiere_decir_carro_con_titulo_salvagelljh5.pdfIn PDF document text
    • http://goproonly.com/nejuxodaxufomonobese72p5q.pdfIn PDF document text
    • http://xotuvezaramapez.22web.org/pawexan.pdfIn PDF document text
    • https://vigoxanumevu.weebly.com/uploads/1/3/4/4/134466257/5566716.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/e4bf4eee-277e-448b-836e-0e8472dd7e42/terupesisidisemu.pdfIn PDF document text
    • http://mowigibimubepi.rf.gd/fivenexevujenibiwek.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4a289b4d-0de6-4980-92f9-0f5eb3b269f2/how_to_calculate_step_down_transformer_kva.pdfIn PDF document text
    • https://09d56968-2ae9-412d-ad86-e67dc63a1c23.filesusr.com/ugd/e8b91f_3bbd5d3ea94f4798a8819d488e8ca00b.pdf?index=trueIn PDF document text
    • https://caa91486-5fcc-43b7-8b2b-5b817ae85bbe.filesusr.com/ugd/26bbcf_54e8f1e2483546dea7081d7c19d6e2ad.pdf?index=trueIn PDF document text
    • https://93bb5028-8b17-4c47-8ab9-f46a024b0e86.filesusr.com/ugd/041612_03fb19d53b7b4774ac4e1fcb2b3636ff.pdf?index=trueIn PDF document text
    • https://3794eb9c-cc8b-492c-aecc-44533f76aaa6.filesusr.com/ugd/1ee69b_462a69b5b1c9486f81dc3ab4cfd2a1ee.pdf?index=trueIn PDF document text
    • https://c370dac7-4848-4fa0-a6df-94361299e8ba.filesusr.com/ugd/fa6303_7b0c9f140247433781e4031b58d363c5.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/273911e0-86ae-4643-92e8-913ca3a71d2a/72496068873.pdfIn PDF document text
    • https://6fc76513-a17a-4053-940d-bef108f5ea85.filesusr.com/ugd/3a5ef0_c1f744874cdc47188da68248488e8c14.pdf?index=trueIn PDF document text
    • https://43a2ba88-5de9-465b-b95f-6a4d82f2d06e.filesusr.com/ugd/dcbeda_30a67c20c27046d59c9ebb4eab85951d.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/8b03e532-b03a-4d01-9401-aeffb81be682/gta_5_update_5_crack_v5_3dm.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_off00010a1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A1D 5196 bytes
SHA-256: 8307ac9d99e420cb6b297cdaed7f7ef55124cfde4e3ecde5ebeb170e4d2039cc
font_01_sfnt_off00011be6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BE6 12516 bytes
SHA-256: d486e72820cff03802934db3ea4dfa03ff1d5a206beeb616470ca3479e26f1cd