Malicious PDF — malware analysis report

Static analysis result for SHA-256 44786f8e8ce5dc1a…

MALICIOUS

PDF

123.2 KB Created: 2021-04-07 09:29:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-20
MD5: 98e0db0f6f180b77b492218701ca81ba SHA-1: bbaf6319683815a65fd0127d0f8b27c7d89c44c2 SHA-256: 44786f8e8ce5dc1af09b47d75307e4ac430b6b86bc1478198acff9c97ff6a5e5
126 Risk Score

Malware Insights

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

The PDF document contains a deceptive title suggesting a Windows update, but analysis reveals it is a link farm designed to redirect users to numerous external websites. The ML classifier strongly indicated maliciousness, and the presence of multiple disposable domains and UTM parameters in the URLs suggests a phishing or SEO spam campaign. No scripts were extracted, but the document's structure and embedded links point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://fokemale.ru/123?utm_term=atualizar+windows+8+para+8.+1 PDF link annotation
    • http://gajonedorebuko.mywebcommunity.org/academic_writing_examples.pdfIn PDF document text
    • http://mobufuwiwid.medianewsonline.com/alkane_nomenclature_practice.pdfIn PDF document text
    • https://widewosum.weebly.com/uploads/1/3/0/7/130775244/gipexemife_kojokup_lilelilipemid.pdfIn PDF document text
    • http://diletemofuvufu.22web.org/rufizipegip.pdfIn PDF document text
    • http://lusuwivaw.medianewsonline.com/mcdonald_s_menu_calories_uk.pdfIn PDF document text
    • https://paluwewokob.weebly.com/uploads/1/3/2/7/132712057/mozanikugazigow_pevemumuweratu_kemorobawe_sugew.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://4e4608fd-868e-43f5-b6ba-14e5e4b50785.filesusr.com/ugd/b1f235_ef72c913fed54c929f6aa796164a4b89.pdf?index=trueIn PDF document text
    • https://b962d5b8-8819-42e3-9ba3-d95e8366760e.filesusr.com/ugd/f51585_4060d5d375d94248a6acb72106bce998.pdf?index=trueIn PDF document text
    • https://c948e902-2437-43f3-9f1e-7aaad30688a7.filesusr.com/ugd/464a75_73a7b3c50d274535b5615f6a89679bdb.pdf?index=trueIn PDF document text
    • http://vixejubofase.epizy.com/propiedades_fisicas_quimicas_y_mecanicas_de_los_materiales_compuestos.pdfIn PDF document text
    • https://3b0fe5ff-7f86-489c-8138-fc984e51136c.filesusr.com/ugd/bfd78a_b759241a1fdc4bc9b54c0d722e2a98fe.pdf?index=trueIn PDF document text
    • https://033a7475-7ccb-45c1-8f1e-38fd320d48d0.filesusr.com/ugd/03a576_8f345eaa928e4e499313b8b21fadc265.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/9be0ddbb-16e2-49ed-ac21-aaeb3a522dae/28329359188.pdfIn PDF document text
    • https://8ed6bd9f-de2b-4923-b7df-82f95eb18a03.filesusr.com/ugd/7fa32f_0a76977ce4da4dca93c1d9b798df4442.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/2d22329d-2f6e-4ab4-950d-6c4b34295584/gukepaj.pdfIn PDF document text
    • https://8eeb1f0a-0cdd-4c66-98a4-83777b49fb54.filesusr.com/ugd/64f9d2_9b7b4b1bdd224903896973cca8572c7a.pdf?index=trueIn PDF document text
    • https://6d4a8fb0-9a8a-4850-8aa1-2b5706121c9a.filesusr.com/ugd/ff2e72_0849bdbb37ff4df4a200488d8b4d9c70.pdf?index=trueIn PDF document text
    • https://uploads.strikinglycdn.com/files/4aa999b5-22c0-4bf8-bbb5-b49a1784913e/486365281.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00018c23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18C23 5360 bytes
SHA-256: d9710d029ad594ce34a993d3eebbdf893ec08e09d1b27b620f777004f46b2e3c
font_01_sfnt_off00019e8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x19E8A 13200 bytes
SHA-256: a46f0ce18dcab04d1de10b6f9fcb1213bd4f23c1b6e0f0be23a580802a19fe13
font_02_sfnt_off0001c909.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1C909 16116 bytes
SHA-256: fe34f531c1343dfad64cea28c90292b70287bdbf16aabb8ead3e349428343eb6