Malicious PDF — malware analysis report

Static analysis result for SHA-256 172b08a46684e30f…

MALICIOUS

PDF

78.2 KB Created: 2021-03-09 20:00:08 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: e51b12d3d441a9b0d8c26cc6f91e3c8c SHA-1: 745292dd014e4d38a4e3f1c007609fb2727393b5 SHA-256: 172b08a46684e30fea24b31c2343a26f8ea2d0115c3ea5b0be58589c1663cb7a
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by a machine learning classifier as malicious and contains a large number of external links, many pointing to potentially untrusted domains. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, suggesting a tactic to manipulate search engine results or distribute further malicious content. While no scripts were extracted, the nature of the link farm suggests it could be used to lure users to phishing sites or download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 5

  • 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://leonvi.ru/award?keyword=bncc+pdf+anos+iniciais PDF link annotation
    • http://ketotreno.buzz/ver_kung_fu_sionhnxmh.pdfIn PDF document text
    • https://gimiduti.weebly.com/uploads/1/3/4/7/134711596/nevevidi.pdfIn PDF document text
    • http://hdsamara.ru/benaletekuliberuwus14rt.pdfIn PDF document text
    • https://tiwirekofer.weebly.com/uploads/1/3/5/3/135314588/zaxuzerufojofasisap.pdfIn PDF document text
    • http://ruluzuzadol.mypressonline.com/pezedakozilagufari.pdfIn PDF document text
    • http://lazujifoxupa.getenjoyment.net/95613719625.pdfIn PDF document text
    • https://vakumijajuxos.weebly.com/uploads/1/3/4/4/134465568/878651.pdfIn PDF document text
    • https://dogixosewe.weebly.com/uploads/1/3/4/6/134633635/8115999.pdfIn PDF document text
    • https://tarutugiwom.weebly.com/uploads/1/3/5/3/135326066/rumixa.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/71d125c5-cabc-4f6e-9d1d-4823b95555e2/60873845644.pdfIn PDF document text
    • https://02bc4616-4eae-4b38-b2c9-0e654f754ee0.filesusr.com/ugd/069df5_a6c756069cc44cc9b8cb189cae8c24b2.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4664cd81-034e-47cf-9851-a8d5748e83da/asus_rt-n12hp_price_in_bangladesh.pdfIn PDF document text
    • https://6c036dbd-b327-4678-b778-de8a2ee7bb50.filesusr.com/ugd/ed64d2_eecf8307b1b24e2dbbed6ccb540ff310.pdf?index=trueIn PDF document text
    • https://76ed6b59-b034-43ac-b949-e1c08f76e3cb.filesusr.com/ugd/ee6100_79ce804c5dfa4919a17cb6e985ded42f.pdf?index=trueIn PDF document text
    • http://rupesujutiwu.myartsonline.com/15193793439.pdfIn PDF document text
    • https://59cf682b-6680-4a08-8b8d-0472bab64ef7.filesusr.com/ugd/d7d6cd_b6664e9605824701adedb64104ece6c8.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d538f744-ee15-4c01-8f8b-ef189e58f818/hunger_games_book_series_age_appropriate.pdfIn PDF document text
    • https://8ecf7690-1f99-4e28-a4b6-3228ba9731d7.filesusr.com/ugd/63d3ad_679e04b780ce4554832e5c88062fd32b.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/d98fd51e-a7d7-46a9-a14f-284ea4a96155/crosman_1077_air_rifle_silencer.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/c579660a-3368-4c09-a6ca-bd12f5c6a662/que_es_lineal_en_literatura.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/dc01bf4b-2d71-4829-aae1-f8ccc08f4e2f/lixovutuvuvoku.pdfIn PDF document text
    • http://zudupaxub.myartsonline.com/rocket_stove_combustion_chamber_design.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_off0000f826.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF826 5072 bytes
SHA-256: 5f9db7e31f4c85e85cf8ba345016ac2e1f1a976c3096b76785f4d1ed5e081d76
font_01_sfnt_off00010982.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10982 10040 bytes
SHA-256: efbcdd1ee2f4399b61905aa2347bd97f02230f1bc91df48eede41a0a9e7847a4