Malicious PDF — malware analysis report

Static analysis result for SHA-256 0ed8c371bd17b61f…

MALICIOUS

PDF

72.9 KB Created: 2021-03-17 05:43:22 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-07-02
MD5: 508c930de939d5a42a7d62ae830e83fc SHA-1: 9cb6164da906187effcdf96eacb50b78afe32ff2 SHA-256: 0ed8c371bd17b61f48028d6afc90451ffa2fe892b56b2071b01902516311e15f
126 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many of which are hosted on disposable domains, indicating a link farm or SEO spam operation. The document body, though heavily obfuscated, contains references to 'convert pdf to word online free' and 'wkhtmltopdf', suggesting a lure to external services. The ML classifier strongly flagged this PDF as malicious, supporting the assessment of a malicious link farm.

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://nipisod.ru/award?keyword=convert+pdf+to+word+online+free+i+love+pdf PDF link annotation
    • https://cdn.sqhk.co/wenewojufaj/ghehfTS/d_day_75_facts_ks2.pdfIn PDF document text
    • https://cdn.sqhk.co/kubepugemaki/dgciaui/brain_balance_locations_tampa.pdfIn PDF document text
    • https://cdn.sqhk.co/mewuxedodi/hihcifd/32109765440.pdfIn PDF document text
    • https://gumewutudeg.weebly.com/uploads/1/3/0/8/130813982/davexaseledo.pdfIn PDF document text
    • https://cdn.sqhk.co/nejijilo/eghgcjj/fibowenorari.pdfIn PDF document text
    • https://bukodagunotul.weebly.com/uploads/1/3/4/0/134012399/riramodedoxakobur.pdfIn PDF document text
    • https://cdn.sqhk.co/vozaxodep/jglDhaU/12895623393.pdfIn PDF document text
    • https://cdn.sqhk.co/toromerepowa/kBjhiBL/padulalu.pdfIn PDF document text
    • https://cdn.sqhk.co/rasetiwulipu/fRemhhZ/weed_wacker_electric_cordless.pdfIn PDF document text
    • https://cdn.sqhk.co/zidexamuwela/ichigiY/51601596356.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/7d7a45db-d301-4742-aad7-d6317352f203/chocolate_museum_warehouse_sale_2020.pdfIn PDF document text
    • https://ea74ff18-003d-4094-8454-8d7e15e33abb.filesusr.com/ugd/50de67_01c47a9c89ad40628522ae14052476d7.pdf?index=trueIn PDF document text
    • https://9480ebe7-8096-4165-94d5-b35dd525e9f4.filesusr.com/ugd/07b43d_b77e5888fbfa485199afda9fdcfe16d5.pdf?index=trueIn PDF document text
    • https://e5baaea7-7007-41de-9367-4ebf3ed55875.filesusr.com/ugd/8e1900_938ff75cb56f4debab09e7dfa1b97034.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/af098a31-1ed8-46e5-8979-e84ebcc2975d/78248563803.pdfIn PDF document text
    • https://s3.amazonaws.com/wixanarer/17442455732.pdfIn PDF document text
    • https://s3.amazonaws.com/mosezavor/83919299756.pdfIn PDF document text
    • https://3df016ad-b40f-424f-9918-b96c60f46212.filesusr.com/ugd/387bfe_cb680c1cb50d4e6bb641ae96ba93b425.pdf?index=trueIn PDF document text
    • https://07bd7893-a6ec-44d5-90fe-c719e602c0bd.filesusr.com/ugd/aafaff_f1cf37caf552443b9ef0e41906cce1a4.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9792910c-9947-4c3c-a985-0518b622a3bf/89831151323.pdfIn PDF document text
    • https://s3.amazonaws.com/gapuruxumeg/what_is_string_in_python_with_example.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/6be55271-ff08-495b-98c3-21435b504d81/which_is_the_best_washing_machine_bosch_or_samsung.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_off0000dfbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFBD 4704 bytes
SHA-256: 7f833f3b250d9c061cbd93c372624d5d9c0222561016ef3ae7b72d5c4836b892
font_01_sfnt_off0000efe4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFE4 11212 bytes
SHA-256: 6dbaaf82670a74565a5c7003781af3597c35b6bf79fac26503ca9535fd746f3c